Front Non-Drive Steering Axle

Directory Previous

Next

Front Non-Drive Steering Axle

Table of Contents

Sub-Headings

Safety 5

Warnings 5

33

Cautions 5

Notes 5

33

33

Introduction 5

Descriptions 5

33

33

Identification 6

Disassembly 8

Drag Link 9

Check/Adjust Wheel Bearings

Steering Arm 10

Adjust Maximum Turn Angle

Tie Rod Arms, Tie Rod Ends 10

Adjust Pressure Relief in Power

34

35

37

Draw Keys/King Pins/Steering

Steering 39

Knuckle 11

Axles with Conventional Wheel Ends 39

King Pin Bushings 13

Hydraulic Pressure Relief 40

Nylon Bushings 13

Turning Radius Angle 40

Preparing Parts for Assembly 14

King Pin Inclination 41

Repair Parts 14

Camber Angle 41

Clean Ground or Polished Parts 15

Caster Angle 42

Clean Rough Parts 15

Adjust Toe-In 43

Dry Cleaned Parts 15

Diagnostics 44

Corrosion Prevention on Cleaned

Lubrication 48

Parts 15

King Pins 50

Install New Fasteners 15

Grease-Lubricated Wheel Bearings 51

Install Original/Used Fasteners 16

Oil Lubricated Wheel Bearings 52

Check Torque Values 16

Inspection and Maintenance 52

Inspect Parts 16

Checking Draw Key Nuts 53

Inspect Wheel Bearings 18

Checking Steering Knuckle End Play 53

Tie Rod Grease Fittings 19

Checking Upper/Lower King Pin 54

55

Assembly 20

Installation 20

Reaming King Pin Bushings 22

Tie Rod End Shop Inspection

Inner Knuckle Bore King Pin Seals 23

Tie Rod Service Tips

Install Knuckle to Axle Beam 24

Tie Rods

Check Steer Knuckle Vertical End 27

Tightening Draw Key Nuts

Draw Key Lock Nuts 28

Checking Steering Arm Bolts

Steering Arm 29

Torque Specifications

Tie Rod Ends into Cross Tube 30

Tie Rod Arms/Cross Tube Assembly 31

Drag Link 32

56

58

59

59

60

60

61

All American Front Axle

1

Directory Previous

Next

Tables

Table A—Front Non-Driving Axle 8

Table B—Axle Wear Limit

Table C—Bushing Reamer

18

Table G—Greasing Intervals 47

Table H—Wheel End Oil Changes 48

Table I—Front Axle with

Conventional Wheel

Dimension

Table D—Camber Angle

Table E—Inspect/Lubrication

23

42

Table J—Special Tools

46

Table F—Lubrication/Inspection 46

62


Next

Exploded View


Figure 1

3


Next

Axle with Conventional Wheel End

Item Description

17

18

19

20

21

22

23

24

25

26

27

11

12

13

14

15

16

3

4

5

6

7

8

9

10

A

B

1

2

28

29

30

31

32

33

34

35

36

Double Nut

Single Nut

Cotter Pin

Castle Nut – Drag Link to

Steering Arm

Steering Arm

Key

Ball Stud

Capscrew and Washer

Grease Fitting

Knuckle Cap – Greaseable

Knuckle Cap – Sealed

Gasket

King Pin Bushing – Easy Steer

King Pin Bushing – Bronze

King Pin Bushing – Nylon

Knuckle

Seal – King Pin Bushing

Castle Nut – Tie Rod Arm to

Knuckle

Cotter Pin

King Pin

Hub Grease Seal

Inner Wheel Bearing Cup

Inner Wheel Bearing Cone

Stud

Hub

Outer Wheel Bearing Cup

Outer Wheel Bearing Cone

Adjusting Nut

Pierced Lock Ring

Lock Washer

Wheel Bearing Nut

“D” Washer

Adjusting Nut

Cotter Pin

Gasket

Hubcap

Capscrew and Washer

Axle Beam

57

58

59

60

61

52

53

54

55

56

47

48

49

50

51

37

38

39

40

41

42

43

44a

44b

45

46

Shims

Tapered Draw Key

Threaded Draw Key

Nut, Threaded Draw Key

Thrust Bearing and “Flat” - Type

Bearing Seal

Thrust Bearing and “Cover” -

Type Bearing Seal

Integral Thrust Bearing and Oil

Seal

Castle Nut – Steering Arm to

Knuckle

Castle Nut (Flared Base) –

Steering Arm to Knuckle

3/4 Inch Stop Bolt

3/4 Inch Jam Nut

1/2 Inch Stop Bolt

1/2 Inch Jam Nut

3/4 Inch Adapter

Washer

Cotter Pin

Square Key

Woodruff Key

Knuckle Tie Rod Arm

Cotter Pin

Castle Nut – Tie Rod Nut to Tie

Rod End

Tie Rod End

Bolt, Clamp

Locknut, Clamp

Clamp, Cross Tube

Cross Tube


Next

Front Axle

Safety

The purpose of this safety summary is twofold. First, it is to help ensure the safety and health of individuals performing service on, or operation of, the Blue Bird All

American Series bus. Second, it is to help protect equipment. Before performing any service or operating procedure on the All

American bus, individuals should read and adhere to the applicable warnings, cautions and notes located throughout this Blue Bird

Service Manual.

Warnings

Warnings apply to a procedure or practice that, if not correctly adhered to, could result in injury or death. Attention should be paid to sections of this manual where warnings appear.

Cautions

Cautions apply to a procedure or practice that, if not correctly adhered to, could result in damage to, or destruction of, equipment.

Notes

Notes are used to explain, clarify or otherwise give additional insight for a given subject, product or procedure. Note that on occasion, notes, too, may advise of potential safety issues.

Introduction

The descriptions and procedures contained in this maintenance manual are applicable to all Meritor front non-drive axles.


Warning

To prevent serious eye injury, always wear safe eye protection when you perform vehicle maintenance or service.

Descriptions

Tie Rod Arm Knuckle and King Pin: The right tie rod arm is a mirror image of the left and both are linked by the cross tube assembly. The right knuckle and king pin assembly is similar to the left, except that it does not have a steering arm attached to it in a manual steering system. A power steering system uses an auxiliary assist cylinder attached to the right knuckle that requires a steering arm in various applications.

Steering Knuckle: Steering knuckles are rated according to the capacity of the front axle. All models use straight king pins.

Steering Arms: The steering arm (usually a forged component) coverts the drag link force into a turning movement through the left king pin through the knuckle.

Pitman Arm: The Pitman arm converts the output torque from the steering gear into the control force applied to the drag link. This linkage component connects the steering gear to the linkage at the center link end.

Tie Rod Assembly: Forged or cast tie rod assemblies are used on Meritor front nondrive steering axles. The tie rod assembly links both steering knuckles for uniform movement and maintains steering control.

Cross Tube and Clamp Assembly: The cross tube and clamp assembly runs approximately parallel to the front axle. The cross tube has right-hand and left-hand threads on the appropriate side of the vehicle. Tie rod clamps secure tie rod ends into the cross tube.

5


Next

Tie Rod Ends: The tie rod ends include a ball joint and boot that thread into the cross tube. Depending on manufacturer design, tie rod ends can be greaseable or nongreaseable. Tie rod ends are either righthand or left-hand threaded and correspond to the inside threads at each end of the cross tube. Figure 2.

Meritor front non-drive steering axles in this manual feature the components found in

Figure 3.

Figure 2

Identification

The entire necessary axle build information, including assembly date, for any Meritor front non-drive axle is indicated on the axle identification tag.

The identification tag is fastened to the center of the beam at the front surface. The axle assembly date is either located in the lower right hand or left hand corner of the tag.

Figure 3

The Julian dating method is currently used to indicate the axle assembly date. The first two digits indicate the year, and the last three digits indicate the day of the year.

.

Figure 4.

For example, "95327" would reflect the

327 th

day of 1995 (November 22 nd

)


Next

Figure 4

To identify the model number, refer to the identification plate on the front of the beam.

Use the complete model number to order parts. Figure 5.

For a description of all models, refer to

Table A.


7


Next

Figure 5

Model

Number

Capacity

(lbs)

Wheel End and Knuckle Type Major Design

Variation

Bottle Spindle with Bolted Tie Rod Arm

Individual Hub, Bearings, Seals

Straight King Pin

Bottle Spindle with Bolted Tie Rod Arm

FF-967 13,200


Straight King Pin

FF-944 13,200


FG-943 14,600


5" Drop from Center of Spindle to Pad and

Special Tie Rods/Easy

Steer™ Design

5" Drop from Center of Spindle to Pad/Easy

Steer™ Design

Table A: Front Non-Driving Axle Model Number Information

Disassembly/Removal

Warning

To prevent serious eye injury, always wear eye protection when you perform vehicle maintenance or service.

Wheel Ends

Warning

Park the vehicle on a level surface. Block the wheels to prevent the vehicle from moving. Support the vehicle with safety stands. Do not work under a vehicle supported only by jacks. Jacks can slip and fall over. Serious personal injury can result.

1. Raise the front of the vehicle until the front wheels are off the floor. Support the vehicle with safety stands.

2. Remove the capscrews that fasten the cap to the hub. Remove the cap and the gasket.

Note

When the adjusting nuts are tightened or loosened, always use the correct size socket to avoid damaging the nut.


Next

3. Remove the fasteners for the wheel bearings. Refer to the following procedure.

Double Nut and Lock Fasteners

a. Bend the tabs of the flattened lock washer away from the wheel bearing nut and the adjusting nut.

Figure 6. b. Remove the wheel bearing nut, the lock washer, the pierced lock ring, and the adjusting nut from the knuckle. Figure 6.

Single Nut Fasteners

a. Remove the cotter pin from the adjusting nut. Figure 7. b. Remove the adjusting nut and the

"D" washer from the spindle.

Figure 7.

4. Remove the outer wheel bearing cone from the hub.

5. Remove the wheel and tire, the hub and the drum as assembly.

Figure 6

Figure 7

6. Remove the brake components per the manufacturer's procedures.

7. Remove the oil seal from the hub.

Remove the inner wheel bearing cone.

8. Inspect the wheel bearings.

Drag Link

Caution

Heating is not an acceptable method for the disassembly of front axle components.

Damage to the axle components could result.

Note

This procedure applies to all axles included in this manual.

1. Remove the cotter pins from the ball studs.

2. Remove the nuts from the ball studs.

3. Disconnect the drag link from the

Pitman arm and the steering arm.

Figure 7.

4. Inspect the drag link.


9


Next

Figure 7

Steering Arm

1. Remove the cotter pin and the nut that fastens the steering arm to the drag link.

Disconnect the steering arm from drag link. Figure 8.

Tie Rod Arms, Tie Rod

Ends and Cross Tube

1. Remove the cotter pins and the nuts that fasten each tie rod end to the tie rod arms. Figure 9.

2. Disconnect the cross tube assembly from the tie rod arms. If available, use tie rod end puller to separate the tie rod end from the tie rod arm. Figure 9.

3. Remove the cotter pin and the nut that fasten the tie rod arms in the knuckle.

Figure 9.

4. Remove the tie rod ends from the knuckle. If necessary, tap on the end of the knuckle with a leather or plastic mallet. Remove the key.

Figure 8

2. Remove the cotter pin and the nut that fastens the steering arm to the knuckle.

3. Remove the steering arm from the knuckle. If necessary, tap on the end of the rod with a leather or plastic mallet.

4. Remove the key from the steering arm.

5. Inspect the steering arm.

Figure 9

5. If necessary, remove the tie rod ends.

Refer to the following procedure.

Figure 10. a. Mark the position each tie rod end is installed in the cross tube. b. Remove the bolts and the nuts from the clamp on the cross tube. c. Remove the tie rod ends from the cross tube.

6. The rotating style clamp on cross tubes can be rotated for easier accessibility when removing the clamp bolt and nut.

Figure 11.

7. Inspect the parts.


Next

Note

All models except FC-901, FC-921, FE-970,

FF-971 and FL-901 use threaded draw keys.

Models FC-901, FC-921, FE-970, FF-971 and FL-901 use plain draw keys.

6. Remove the plain or the threaded draw keys. Refer to the following procedure.

Figure 10

Figure 11

Draw Keys, King Pins and Steering Knuckle

1. Remove the wheel ends as described in this section.

2. Vent the air from the brake system.

Disconnect the air lines from the brakes.

3. Remove the brake components. Refer to procedures from the brake manufacturer.

4. Remove the tie rod arms and the steering arm (left side) from the knuckle. Refer to the procedure in this section.

5. Remove the capscrews that fasten the kin pin caps to the top and the bottom of the knuckle. Remove the caps and the gaskets. Figure 12.


Figure 12

Remove Plain Draw Keys

Warning

Use a brass or leather mallet for assembly and disassembly procedures. Do not hit steel parts with a steel hammer. Pieces of a part can break off and cause serious personal injury.

Use a brass hammer and a steel drift to remove the draw key. Place the drift on the small ("D"-shaped) end of the key. Figure

13.

Remove Threaded Draw Keys

a. Loosen the threaded draw key lock nut until the top of the lock nut is even with the end of the draw key.

11


Next

b. Use a brass drift and a hammer to hit the end of the draw key. Figure

14. c. Remove the nut from the draw key.

Remove the draw key from the knuckle.

Warning


Caution

Force must be directly applied to the bottom of the nut and the end of the key. If force is not directly applied, the draw key will be damaged.

Note

If the bushings are not being replaced, perform the following to prevent damaging the bushing during kin pin removal.

• Remove any flaring on the drift that may touch the bushings.

• Wrap tape to a thickness of 1/16 inch

(1.5 mm) on the end of the drift.

7. Use a brass drift and a hammer to remove the king pins from the knuckle.

Figure 15.

If the king pin is hard to remove, use a hydraulic king pin remover. Refer to

Table J in Special Tools section.

Warning

Wear gloves when you remove or install shims. Shims have sharp edges that can

cause injury.

Figure 13

Figure 14

Figure 15


Next

8. Remove the knuckle from the axle beam. Remove the shims, the thrust bearing, and the seal between the beam and the knuckle. Figure 16.

9. Inspect the parts.

Nylon Bushings

Remove the top and the bottom bushing from the knuckle bore. Figure 18.

Figure 16

King Pin Bushings

1. Remove and discard the lower king pin seal. Figure 17.

2. Turn knuckle upside down and remove the upper king pin seal.

Figure 17

3. Remove the old bushings as follows.


Figure 18

Easy Steer™ and Bronze

Bushings

Warning

Observe all warnings and cautions provided by the press manufacturer to avoid damage to components and serious personal injury.

Note

On FF-, FG-, and FL-Series axles, the bushings can be removed with Bushing

Service Kit from Kent-Moore Tools. Refer to Table J in Special Tools section.

a. Make a tool to remove the bushings.

Figure 19. b. Place the knuckle in a vise. Use a press with a 5-ton capacity. Make sure the knuckle does not move when the bushings are removed. c. Install the tool into the upper king pin bushing. Press the upper king

13


Next

pin bushing from the knuckle bore.

Figure 20. d. Turn knuckle upside down and install the tool in the lower king pin bushing. Press the lower bushing from the knuckle bore. Figure 20.

Axle Model

Number

Figure 20

Dimension X

(+ 0.001 in) (+0.025 mm)

Dimension Y

(+ 0.001 in) (+ 0.025 mm)

Figure 19 - Dimensions for Bushing Removal and Installation Tool

Preparing Parts for

Assembly

Warning


Repair Parts

The repair or reconditioning of front axle components is not allowed. Meritor recommends replacing damaged or out-ofspecification components. All major components are heat treated and tempered.

Caution

Do not bend, weld, or heat any front axle component. If the axle is bent, welded or heated, the strength of the axle is reduced and the warranty is voided. An axle damaged by bending, welding, or heating may cause a vehicle accident and serious personal injury.

The following operations are prohibited on front axle components.

1. Welding of or to the steering arms, tie rod arms, the knuckles, the king pins, the axle beams, the tied rod assemblies, the hubs, the drums, or the brakes.

2. Hot or cold bending of the knuckles, the steering arms, the tie rod arms, the ball studs, the axle beams or the tie rod assemblies.


Next

3. Drilling out of the holes in the axle beam for the king pins.

4. Drilling out of the draw key holds in the knuckle.

5. Spray welding of bearing diameters on the knuckles or in the machined bores.

6. Disassembly of unitized truck hub unit.

7. Milling or machining of any component.

Clean Ground or Polished

Parts

Warning

Solvent cleaners can be flammable, poisonous and cause burns. Examples of solvent cleaners are carbon tetrachloride, emulsion-type cleaners, and petroleumbased cleaners. To avoid serious personal injury when you use solvent cleaners, you must carefully follow the manufacturer's product instructions and these procedures.

• Wear safe eye protection

• Wear clothing that protects your skin.

• Work in a well-ventilated area.

• Do not use gasoline, or solvents that

contain gasoline. Gasoline can explode.

• You must use hot solution tanks or

alkaline solutions correctly. Follow the manufacturer's instructions carefully.

Use a cleaning solvent to clean ground or polished parts and surfaces. Kerosene or diesel fuel can be used for this purpose. Do not use gasoline.

Do not clean ground or polished parts in a hot solution tank or with water, steam, or alkaline solutions. These solutions will cause corrosion of the parts.

Clean Rough Parts

Rough parts can be cleaned with the ground or polished parts. Rough parts also can be cleaned in hot solution tanks with a weak alkaline solution. Parts must remain in the hot solution tanks until they are completely cleaned and heated.

Dry Cleaned Parts

Parts must be dried immediately after cleaning. Dry parts with clean paper or rages, or compressed air. Do not dry bearings by spinning with compressed air.

Corrosion Prevention on

Cleaned Parts

Apply light oil to cleaned and dried parts that are not damaged and are to be immediately assembled. Do NOT apply oil to the brake linings or the brake drums.

If parts are to be stored, apply a good corrosion preventative to all surfaces. Do

NOT apply the material to the brake linings or the brake drums. Store the parts inside special paper or other material that prevents corrosion.

Note

Be sure that all tapered joints are clean and dry with no lubrication or corrosion

preventative applied to mating surfaces.

Install New Fasteners with Pre-applied

Adhesive Patches

1. Clean the oil and dirt from threaded holes. Use wire brush to remove old patch material. There is no special cleaning required.

Caution

Do not apply adhesives or sealants on new fasteners with pre-applied adhesive patches or in the threaded holes. If other adhesives or sealants are used, the new adhesive will not function correctly.


15


Next

2. Assemble parts using the new preapplied adhesive fasteners.

Note

There is no drying time required for

fasteners with pre-applied adhesive.

3. Tighten the fasteners to the required torque value for that size fastener. Refer to Table I in Torque Specification section.

Install Original or Used

Fasteners Using Meritor

Liquid Adhesive 2297-C-

7049 or Loctite® 680 or

Equivalent

1. Clean the oil, dirt, and old adhesive from all threads and threaded holes.

Use a wire brush.

Caution

Do not apply adhesive to fastener threads that will be installed into a closed bore. As the fastener is installed, air pressure will force adhesive applied to fastener out of the closed bore. Apply adhesive into threaded

bore only.

2. Apply four or five drops of Meritor

Liquid Adhesive, Loctite® 680, or equivalent to each threaded hole or bore

ONLY. Make sure the adhesive is applied to the threads.

3. Tighten the fasteners to the required torque value for that size fastener.

Note

There is no drying time required for Meritor

Liquid Adhesive 2297-C-7049, Loctite®

680, or equivalent.

Check the Torque Values of Dri-Loc Fasteners Not

Requiring Removal

Note

If Dri-Loc fasteners do not require removal from components, check the fasteners for correct torque value as follows.

1. Apply the MINIMUM amount of torque required for that size fastener. The fastener MUST NOT rotate.

2. If the fastener rotates any amount, remove the fastener from the component. Inspect the fastener and the hole for wear and damage. Repair as necessary. If the fastener and the hole are in good condition, apply adhesive to the threaded hole. Follow the procedure for installing old Dri-Loc fasteners.

Inspect the Parts

Carefully inspect all disassembled parts before assembly. Refer to the following guidelines.

1. Inspect and replace any parts that are worn, cracked, or damaged. Check for cracks using dye penetrant, magnetic flux, or fluorescent particle testing methods.

2. Remove the old bushing from the knuckle. Measure the upper knuckle bore inside diameter at two locations.

Always use a micrometer and a telescoping gauge when taking knuckle bore measurements. Some rounding of the top and bottom bore edges is acceptable.

Measure the bore in four positions and at two locations. The two locations must be 90 degrees opposed from each other. Figure 20. If the average measurement is more than the Knuckle

Bore Maximum Diameter specification in Table B, replace the knuckle.


Next

Figure 20

Repeat this procedure for measuring the lower knuckle bore. Figure 21. Refer to the Knuckle Bore Maximum

Diameter indicated in Table B. Verify the average inside bore dimension does not exceed the Knuckle Bore Maximum

Diameter specifications.

Measurements taken at either the upper or the lower knuckle bores, which exceed the Knuckle Bore Maximum

Diameter in Table B, indicate the knuckle requires removal and replacement.

3. Measure the king pin bushing inside diameter using a micrometer and a telescoping gauge for taking measurements.

If the average inside diameter measurement is greater than the King

Pin Bushing Maximum Inner Diameter

Table B, install a new bushing.

Measure the inner diameter of the new bushing after installation and reaming.

Measure the inner diameter of the bushing in four positions and at two locations. The two locations must be 90 degrees opposed from each other.

Figure 20. If the average measurement is more than the King Pin Bushing

Maximum Inner Diameter specification in Table B, replace the bushing.

4. Measure the inner bore diameter of the axle beam. Rounding at the top and bottom of the beam is acceptable.

Measure the axle beam bore at four positions, Figure 20, and at two specific locations: 1/2 inch (12.7 mm) below the top of the bore and 1/2 inch (12.7 mm) above the bottom of the bore. Figure

22.

If the average measurement is greater than the Axle Beam Bore Maximum

Diameter given in Table B, the entire axle beam requires replacement.

Figure 21


17


Next

Figure 22

Model

Number

Knuckle

Bore

Max.

Diameter

Beam

Bore

Max.

Diameter

King Pin

Bushing

Max

Inner

Diameter

FF-966

1.9220 inch

(48.818 mm)

1.7980 inch

(45.6692 mm)

1.7960 inch

(45.6180 mm)

FF-967

FF-944

FF-943

1.9220 inch

(48.818 mm)

1.9220 inch

(48.818 mm)

1.9220 inch

(48.818 mm)

1.7980 inch

(45.6692 mm)

1.7980 inch

(45.67692

mm)

1.7980 inch

(45.6692 mm)

1.7960 inch

(45.6180 mm)

1.7960 inch

(45.6180 mm)

1.7960 inch

(45.6180 mm)

Table B – Axle Wear Limit Specifications

Inspect the Wheel

Bearings

Inspect the wheel bearings when the hub is removed from the knuckle spindle.

Remove all lubricant from the bearings, knuckle, hub, and hubcap.

Inspect the cup, the cone and the rollers and cage of all bearings. If any of the following conditions exist, the bearing MUST be replaced.

1. The center of the large diameter end of the rollers is worn level or below the outer surface. Figure 23.

2. The radius at the large diameter end of the rollers is worn to a sharp edge.

Figure 23.

• A visible roller groove in the cup or the cone inner race surfaces. The groove can be seen at the small or large diameter end of both parts.

Figure 24.

• Deep cracks or breaks in the cup, the cone inner race, or the roller surfaces. Figure 24.

• Bright wear marks on the outer surface of the roller cage. Figure

25.

• Damage on the rollers and on the surfaces of the cup and the cone inner race that touch the rollers.

Figure 26.

• Damage on the cup and the cone inner surfaces that touch the rollers.

Figure 27.

Figure 23


Next

Figure 24

Figure 27

Tie Rod Grease Fittings

When inspecting the tie rod, observe the following.

1. If a grease fitting is missing, install a new one. Do not attempt to install a fitting if the tie rod end is a nongreaseable design. Figure 28.

2. Tighten all grease fittings to the specified torque. Figure 29.

Figure 25

Figure 26


Figure 28

19


Next

2. Be sure that the bushing lube slots align with the grease ports in the knuckle.

Figure 30.

Assembly

Figure 29

Warning


Installation

King Pin Bushings

Nylon Bushings

Insert the nylon bushing in each knuckle bore by hand. Be sure that the entire outer surface of the nylon bushing is in contact with the knuckle bore.

Check the nylon bushing installation before attempting to install the knuckle to the axle beam noting the following.

1. Verify that each nylon bushing is fully seated in the knuckle bore by passing the king pin through the upper and lower bores after insertion.

Note

The nylon bushing installation is not a press fit in the knuckle bore as in cases where a

bronze or Easy Steer™ bushing issued.

Figure 30

Bronze and Easy Steer™

King Pin Bushings—Axles with Conventional Wheel

Ends

Without a Press

Note

On the FF-, FG- and FL- Series axles, the bushings can be installed without a press.

Use the Bushing Service Kit from Kent

Moore Tools to install and ream the bushings.

Bronze and Easy Steer™ bushings have an interference fit in the knuckle bores and require a suitable installation tool for bushing installation. Figure 31.


Next

Figure 31

Position the bushings into outer end(s) of the knuckle bores. Install to proper position using selected installation tool. Figure 32.

Ream the Easy Steer™ bushings after installation into the knuckle. top of the press. Make sure tops of the bores are parallel to the top of the press.

3. Place new bushing in the upper knuckle bore.

4. Using installation tool, press start the bushing 1/8 inch (3 mm) into the upper bore. Release the pressure. Make sure the bushing is straight into the upper bore. Figure 33.

Figure 32

With a Press

1. Install the top king pin bushing first.

Warning

Observe all warnings and cautions provided by the press manufacturer to avoid damage

to components and serious personal injury.

2. Put the knuckle in a press, if used, so that the top of the knuckle is toward the

Figure 33

5. On Easy Steer™ bushings and for MFS axles, press the bushing farther to a depth of 0.352- to 0.382-inch (8.94-9.70 m) below the top of the upper knuckle bore. Figure 34.

6. Turn the knuckle over so that the bottom of the knuckle is up. Make sure the bore is parallel to the top of the press.


21


Next

Note

Reamer tools are available from SPX-Kent

Moore at 1-800-328-6657 and from Wright

Tool Company at 1-800-783-9826.

1. Place the knuckle in a vise with brass jaws. the reamer tool.

Figure 34

7. Place new bushing in lower knuckle bore.

8. Using installation tool, press start the bushing 1/8 inch (3 mm) into the lower bore. Release the pressure. Make sure the bushing is straight into the lower bore. Figure 33.

9. On Easy Steer™ bushings, press the bushing farther to a depth of 0.352- to

0.382-inch (8.94-9.70 mm) below the top of the lower knuckle bore (as viewed with the knuckle upside down). Figure

34.

10. Ream the bushings. Refer to the procedures in this section.

Reaming the King Pin

Bushings

Bronze and Easy Steer™

Bushings

Caution

Do not hone or burnish the bushings. The bushings will be damaged by honing or burnishing.

Figure 35

3. Slide the pilot of the reamer through the top bushing until the reamer blades touch the bushing. Figure 36.

4. Rotate the reamer with a light downward pressure. Do not apply too much force. Rotate the reamer smoothly.

5. After the reamer cuts most of the top bushing, make sure the tool does not drop to the bottom bushing.

6. After cutting the top bushing, guide the reamer into the bottom bushing. Repeat

Steps 3-5. Figure 37.

7. Slide the reamer out of the bottom bushing. If the reamer must be removed through the top bushing, rotate the tool in the opposite cutting direction.

8. Clean all material from the bushings.


Next

Axle

Model

Lower Pilot

Diameter

Dimension

"A" (- 0.001 inch or +

0.0245 mm)

Bushing Reamer Dimensions

Blade

Diameter

Dimension "B"

(+0.001-inch or +0.0245 mm)

Upper Pilot

Diameter "C"

(+0.001 inch or

+0.0245 mm)

Lower Pilot

Length

Dimension "D"

Upper Pilot

Length

Minimum

Dimension "E"

FF-966 1.7800 45.2120 1.7955 45.6057 1.7900 45.4660 10.25 260.35 12.25 311.15

FF-967 1.7800 45.2120 1.7955 45.6057 1.7900 45.4660 10.25 260.35 12.25 311.15

FF-944 1.7800 45.2120 1.7955 45.6057 1.7900 45.4660 10.25 260.35 12.25 311.15

FG-943 1.7800 45.2120 1.7955 45.6057 1.7900 45.4660 10.25 260.35 12.25 311.15

Table C: Bushing Reamer Dimensions

Figure 36

Figure 37

Inner Knuckle Bore King

Pin Seals

1. Place the top of the knuckle in a vise with brass jaws. The bottom of the knuckle must be toward you.

2. Place the seal in the bottom of the top knuckle bore. The lip of the seal must be away from the bore. Figure 38.


23


Next

Figure 38

3. Place the end cap for the knuckle on top of the seal. Slide the king pin through the opposite knuckle bore. Use the king pin to install the seal. Figure 39.

For Easy Steer™ and nylon bushing, make sure the top of the seal is even with top of the knuckle. Figure 40.

Figure 40

4. Turn the knuckle over in the vise. The jaws of the vise must hold the bottom of the knuckle, and the top of the knuckle must be toward you.

5. Place the seal in the top of the bottom knuckle bore. The lip of the seal must be away from the bore. Figure 38.

6. Repeat step 3 of this procedure.

Install the Knuckle to

Axle Beam

1. Clean the bores of the knuckle and the axle beam.

2. Install the seal on the thrust bearing.

On "cover" type seals, install the seal over the open end of the bearing.

Figure 41.

On "flat" type seals, put the seal over the closed part of the bearing. Figure 41.

Figure 39


Next

Figure 41

Integral Thrust Bearing and Seal

The one-piece thrust bearing with an integrated grease seal is completely interchangeable with the two-piece design. It has a specified top and bottom orientation.

• The surface with the inner diameter seal must be on top.

• The surface with the outer diameter seal must be on the bottom. Figure

42.

Figure 42

3. Place the seal and thrust bearing assembly on the inner knuckle. Make sure the seal will face upward toward the beam. The top inner diameter will be in contact with the bottom of axle beam. Figure 43.


Figure 43

Warning

Wear gloves when you install shims. Shims have sharp edges that can cause injury.

25


Next

4. Inspect the shims for damage before reinstallation, noting the following.

• Replace damaged shims with same size shims (or in combination) that allow the least amount of knuckle end play.

• If a new shim pack must be determined, select the amount of shims that will give the least amount of end play.

5. After inspection, place shims on top of axle beam bore machined surface.

Align shims for king pin installation.

6. Place the knuckle on the axle beam.

7. Place a pry bar between the steering arm boss and the axle beam. Lift the knuckle and slide the shim pack between the top of the beam and the knuckle. Figure 44.

• Make sure all the bores are aligned.

If the bores are not aligned, the parts will be damaged when the king pin is installed.

• Remove the pry bar.

• Before placing the king pin into the top of the knuckle, be sure the word

"TOP" (which is stamped on the king pin) can be seen. Figure 45.

• Rotate king pin so that two draw key slots of pin properly align with draw key slots in the knuckle.

Figure 44

8. Before installing the king pin into the top of the knuckle, be sure to note the following.

• Apply the specified lubricant to bottom half of king pin.

Figure 45

Caution

Do not force the pin through the top bushing or the shims will be damaged.

9. Install the king pin into the top of the knuckle and through the area where shims are located.

Warning


10. If required, use a hammer and a brass drift to apply direct force to king pin for seating it into the lower knuckle bore.


Next

Note

Do not drive or tighten the draw keys into the knuckle until the end play is checked and adjusted.

Note

All models except FC-901, FC-921, FE-970,

FF-971 and FL-901 use threaded draw keys.

Models FC-901, FC-921, FE-970, FF-971 and FL-901 use plain draw keys.

11. Seat top draw key into front of beam.

Seat bottom draw key in back of beam by striking with hammer and drift.

Make sure keys align with slots of king pin. Do not install or tighten lock nuts before checking the knuckle end play.

Figure 45A.

Figure 46

3. Attach a dial indicator. Place the base on the knuckle. Place the tip on the center of the king pin. Set the dial indicator on "zero" (0). Figure 47.

Figure 45A

Check the Steer Knuckle

Vertical End Play for Shim

Selection

1. Strike the boss of the knuckle with a rubber mallet to move the parts in position. Figure 46.

2. Turn the knuckle to the straight

(forward) position.

Figure 47

Warning

If a hydraulic jack is used to measure end play, use two safety stands to support the axle in the rest position. If safety stands are not used, the axle can fall. Serious personal injury can occur.

4. Use one of the following procedures to measure the end play.

• Place a pry bar between the knuckle and the top of the axle center. Push


27


Next

the knuckle up and measure the end play. Figure 48.

• Place a block of wood and a hydraulic jack under the bottom of the knuckle. Raise the knuckle until the pointer on the dial indicator stops. Figure 49.

Figure 48

5. Repeat Steps 3 and 4 with the axle in the full right and full left turn positions.

6. The end play must be 0.001 to 0.025 inch (0.025-0.635 mm) in all positions.

If the knuckle binds or "0" (zero) end play is measured, remove the shims from the shim pack.

If more than 0.025-inch (0.635 mm) end play is measured, add shims to the shim pack.

Draw Key Lock Nuts

Warning


Caution

Make sure the draw key is installed completely or the lock nut is tightened to the specified torque. If not installed correctly, the king pin and the axle beam will be damaged.

Note

All models except FE-970, FF-971 and FL-

901 use threaded draw keys. Models FE-

970, FF-971 and FL-901 use plain draw keys.

1. Install the draw keys. Refer to the following procedure.

Plain Draw Keys

Use a hammer and a brass drift to install the draw key in the axle beam and knuckle. Make sure the key is installed

1/32 to 1/8 inch (1-3 mm) below the outer surface of the beam. Figure 50.

Threaded Draw Keys

On threaded draw keys, install the lock nut and tighten to 30-45 lb-ft (41-61

N•m). Figure 51.

2. Install new gaskets and the caps on the top and the bottom of the knuckle.

Install the capscrews and the washers and tighten to 20-30 lb-ft (28-40 N•m).

Figure 52.

3. Connect the tie rod arm to the knuckle.

Refer to the procedure in this section.

Figure 49


Next

Figure 50

Figure 51

Figure 52

Steering Arm

1. Press the key in the slot in the arm.

2. Install the steering arm in the knuckle.

Caution

Tighten the nuts to the specified torque. If the nuts are not tightened to the specified torque, the parts will be damaged.

3. Install the nuts. Tighten to the specified torque. Refer to Table I in Torque

Specification section.

4. Install the cotter pins. If necessary, tighten the nut until the holes are aligned. Do not loosen the nut to install the cotter pin.

5. Lubricate the drag link end that connects to steering arm. Refer to Lubrication section

6. Check for correct operation.


29


Next

Figure 53

Tie Rod Ends into the

Cross Tube

Refer to Figure 54

Figure 55

1. If you are only replacing the cross

tube: When replacing the cross tube, be certain that the replacement cross tubes is properly specified from OE manufacturing standards. The

Figure 54

Note

The cross tube has right-hand threads on the right side of the vehicle and left-hand threads on the left side of the vehicle. Make sure the tie rod end threads are correctly installed into the tube deeper than the end of the cross tube slot. Figure 55.

replacement tube should have the same length and diameter as the original removed tube that couples with the tie rod ends. Use the thread count as a guide and install the tie rod ends into the threaded cross tube ends to the approximate depth marked during the tie rod assembly removal.

Both tie rod ends must be installed into the cross tube deeper than the end of the cross tube slot. Figure 56.

2. If you are installing new tie rod ends:

Thread the tie rod ends to the approximate original depth inside the cross tube. Figure 56.

Both tie rod ends must be installed into the cross tube deeper than the end of the cross tube slot. Figure 56.

3. Install the nuts and the bolts in the clamps. Tighten to the specified torque.


Next

Figure 55. Refer to Torque

Specification section.

4. Check that the tab on the clamps is firmly seated against the end of the cross tube. Figure 59.

Figure 56

Tie Rod Arms, Tie Rod

Ends and Cross Tube

Assembly

Note

If a different tie rod arm is installed (such as for increasing the maximum turn angle), the steering geometry is changed and may cause tire wear. Contact your Meritor service representative.

1. Press the key in the slot in the arm.

Figure 57.

2. Install the tie rod arm in the knuckle.

Figure 57.

Figure 57

Caution


3. Install the nut on the tie rod arm.

Tighten to the specified torque. Refer to

Table I in Torque Specification section.

4. Install the cotter pins. If necessary, tighten the nut slightly, increasing the final torque value until the holes are


31


Next

aligned. Do not loosen the nut to install the cotter pin.

Note

The cross tube has right-hand threads on one end and left-hand threads on the other end. Make sure the ends are installed on the tube.

5. If removed, install the tie rod ends on the cross tube to the position marked during removal.

If new tie rod ends are installed, thread the ends equally on the cross tube to the required length. Figure 58.

6. Install the nuts and the bolts in the clamps. Tighten to the specified torque.

Refer to Table I in Torque Specification section. Figure 58.

Figure 58

7. The rotating style clamp on cross tubes can be rotated for easier accessibility when installing the clamp bolt and nut.

Tighten nut sufficiently to engage the locking element of the nut with the bolt.

Clamp and tie rod end must be free to rotate. Make certain the clamp tab is firmly seated against the cross tube.

Figure 59.

Figure 59

8. Clean and dry tie rod taper and connect the tie rod ends into the tie rod arms.

The threaded portion of the tie rod end must be installed into the cross tube beyond the end of the slot. Make certain the clamp tab is firmly seated against the cross tube.

9. Install the nuts on the tie rod ends.

Tighten to the specified torque. Refer to

Table I in Torque Specification section.


11. Check and, if necessary, adjust the toein.

Drag Link

1. Connect the drag link to the steering arm. Figure 60.

2. Connect the drag link to the Pitman arm.

Caution


3. Install the nuts. Tighten to the specified torque. Refer to Torque Specification section.


Next


5. Lubricate the drag link. Refer to

Lubrication section.

6. Check for correct operation.

Figure 60

Install the Brake

Components and Wheel

Ends

1. Install the brake assembly on the knuckle.

2. Lubricate the wheel bearings. Refer to

Lubrication section

3. Install the outer wheel bearing cone in the hub. Install the adjusting nut.

4. Adjust the wheel bearings. Refer to section entitled "Check and Adjust the

Wheel Bearings". Refer to the wheel end hardware manufacturer's procedures if necessary.

5. Install the cap and the gasket on the hub.

Install the capscrews and tighten to 20-

30 lb-ft (27-41 N•m).

6. Install the wheel and tire assembly.

7. Lower the vehicle to the ground. Check for correct operation.

8. Check and adjust the toe-in.

Adjustments

Warning


Inspection Before Alignment

Check the following before doing a front wheel alignment.

Inspection

Refer to section on Lubrication, Inspection and Maintenance.

Wheels and Tires

Check the following items.

• Make sure the tires are inflated to the specified pressure.

• Make sure the front tires are the same size and type.

• Make sure the lug nuts are tightened to the specified torque.

• Make sure the wheels are balanced.

• Check for bent or damaged wheels.

Front Suspension

Check for the following items.

• Make sure all fasteners are tightened to the specified torque.

• Inspect the leaf springs for wear and damage.

• Inspect the shock absorbers for wear and damage.

Rear Axle and Rear

Suspension

Front tire wear can be caused by the rear axle. If the outer edge of one front tire is


33


Next

worn and the inner edge of the other front tire is worn, check the following.

• Make sure all fasteners are tightened to the specified torque.

• Make sure the leaf springs are not worn or damaged.

• Make sure the bushings in the leaf springs are not worn or damaged.

• Make sure the torque rods (if used) are correctly adjusted.

• Make sure the frame is not bent.

• Make sure the rear axle (especially a tandem axle) is correctly aligned.

• Refer to any additional rear axle and suspension recommendations and specifications from Blue Bird

Corporation.

Front Wheel Alignment

Check the front wheel alignment when the following occur.

• Every 200,000 miles (320 000 km) or 24 months (normal maintenance).

• When the vehicle does not steer correctly.

• To correct a tire wear condition.

Minor Front Wheel

Alignment

Perform a minor front wheel alignment for all normal maintenance conditions.

Perform the minor front wheel alignment in the following sequence.

1. Inspect all the systems that affect the wheel alignment. Refer to "Inspection

Before Alignment" in this section.

2. Check and adjust the wheel bearings or wheel bearing end ply for the truck hub unit.

3. Check and adjust the toe-in.

Major Front Wheel

Adjustment

Perform a major front wheel alignment to correct steering and tire wear conditions.

To perform the major front wheel alignment, refer to the following sequence.

1. Inspect all the systems that affect the wheel alignment. Refer to section entitled "Inspection Before Alignment".

2. Check and adjust the wheel bearings.

For models with unitized hubs, check wheel bearing end play for the truck hub unit. Refer to section entitled

"Inspection of Sealed Hub Units" under

Lubrication, Inspection and

Maintenance.

3. Check and adjust the maximum turn angle.

4. If the vehicle has power steering, check and adjust the pressure relief in the power steering system. Refer to the procedure "Adjust the Pressure Relief in the Power Steering System (Setting the

Maximum Turn Angle)" in this section.

5. Check and adjust the turning radius angle (toe-out on turns or Ackerman angle). Refer to "Turning Radius

Angle" in this section.

6. Check the king pin (or steering axis inclination. Refer to "King Pin

Inclination" in this section.

7. Check the camber angle. Refer to

"Camber Angle" in this section.

Caution

Axle camber is not adjustable. Do not change the axle camber angle or bend the axle beam. Bending the axle beam to change the camber angle can damage the axle and reduce axle strength, and will void

Meritor's warranty. A bent axle beam can also cause a vehicle accident and serious personal injury.

8. Check and adjust the caster angle. Refer to "Caster Angle" in this section.


Next

9. Check and adjust the toe-in. Refer to

"Adjust the Toe-In" in this section.

Check and Adjust the Wheel

Bearings

Warning


1. Raise the vehicle so that the wheels are off the floor. Support the vehicle with safety stands.

2. Remove the capscrews and remove the gasket and the cap from the hub.

3. Make sure that the brake drum and the hub fasteners are tightened to the manufacturer's specifications.

4. Attach a dial indicator with the magnetic base at the bottom of the hub or the brake drum. Adjust the dial indicator so that the pointer is against the center of the knuckle. Set the dial indicator on

"zero" (0). Figure 61.

Note

Do not push/pull at the top and the bottom of the hub or drum. Pushing or pulling at the top and the bottom will not give a true reading of the end play.

5. Measure the end play by pushing/pulling on each side of the hub or drum while looking at the dial indicator. The end play is the total travel observed. If the end play is not within 0.001- to 0.005inch (0.025-0.127 mm), adjust the wheel bearings. Figure 61.

Figure 61

6. If necessary, adjust the wheel bearings.

7. On Double Nut and Lock fasteners, bend the lock washer off the wheel bearing nut. Remove the wheel bearing nut, the lock washer and the pierced lock ring. Figure 62.

On Single Nut Fasteners, remove the cotter pin from the adjusting nut.

Figure 63.

Figure 62


35


Next

Note

When removing or installing the adjusting nuts, use the correct wrench socket to avoid damaging the adjusting nuts.

8. Use a torque wrench to tighten the adjusting nut to 100 lb-ft (136 N•m) while rotating the tire in both directions.

Figure 64.

Caution

Do not strike the adjusting nut with a metal hammer. Do not use a hammer and chisel or drift, or loosen the adjusting nut. This will damage the nut.

9. Loosen the nut completely and then tighten the nut to 20 lb-ft (27N•m) while rotating the tire. Figure 64.

Figure 64

10. Axles with Single Nut Fasteners. a. Back off the adjusting nut 1/8 turn.

Figure 65. b. Rotate the nut in either direction to line up a slot with the closest cotter pin hole in the spindle. c. Install a new cotter pin in the nut. d. Measure the end play. The end play must be 0.001-0.005 inch (0.025-

0.127 mm). Refer to Steps 4-5.

Readjust if necessary.

Figure 63

Figure 65


Next

11. Axles with Double Nut and Lock

fasteners. a. Back off the adjusting nut 1/3 turn.

Figure 65. b. Install the pierced lock ring, the lock washer and the wheel bearing nut. c. For wheel bearing nuts in sizes from

1 1/8 inches up to 2 5/8 inches, tighten to 200-300 lb-ft (271-407

N•m). For wheel bearing nuts 2 5/8 inches and more, tighten to 250-400 lb-ft (339-542 N•m). d. Measure the end play. The end play must be 0.001-0.005 inch (0.025-

0.127 mm). Refer to Steps 4-5.

Readjust if necessary. e. If end play is to specification, bend washer to at least one flat edge of outer wheel bearing nut. Figure 62.

12. Install the gasket and the cap on the hub.

Install the capscrews and tighten to 20-

30 lb-ft (27-41 N•m).

13. Lower the vehicle to the ground. Check the correct vehicle operation.

Adjust the Maximum

Turn Angle

The stop bolt on the back of the knuckle controls the maximum turn angle.

Caution

Do not exceed the maximum turn angle specified by the vehicle manufacturer. If the angle is exceeded, the steering arms, the cross tube and the tie rod ends will be damaged.

Check the angle if the front tires rub against the frame or if the steering gear has been serviced. Use an alignment machine to check the angle. Refer to procedures from the manufacturer of the alignment equipment.


For power steering systems, the stop bolt should NOT touch the beam. The stop bolt should always have a minimum clearance of

1/8 inch (3 mm) when the knuckle is in the full-turn position. Figure 66.

Figure 66

For manual steering systems, Meritor recommends a stop bolt clearance of 1/8 inch (3 mm). Stop bolt contact is acceptable if no other stops are used for the maximum turn angle of the steering knuckle.

Caution

If the stop bolt is missing, bent or broken, the system requires adjustment. Refer to

"Mechanical Stop" in this section.

Note

If the steering system is out-of-adjustment, inspect the steering arm for damage. Use a magnetic particle or liquid dye penetrant inspection procedure to inspect the steering arm. Pay particular attention to the bend, the taper and the area near the ball stud.

Refer to the manual from Blue Bird for additional inspection procedures.

37


Next

Caution

In power steering systems, the hydraulic pressure should relieve or "drop off" at the end of the steering stroke (with 1/8 inch or 3 mm minimum clearance at the stop bolt). If the pressure does not relieve, the components of the front axle will be damaged.

Two-Piece Steering 3/4-Inch Stop Bolt

1. Put a 1/8-inch (3 mm) spacer between the stop bolt and the boss on the axle beam.

2. Turn the steering wheel until the boss on the axle beam touches the spacer in front of the stop bolt. Figure 67.

3. If the maximum turn angle does not meet vehicle manufacturer's specifications, correct the maximum angle. In a power steering system, adjust the pressure relief. In a manual steering system, follow guidelines and specifications from Blue Bird.

Figure 67

4. When the maximum turn angle is correct: Figure 67. a. Loosen stop bolt jam nut. b. Insert 1/8 inch spacer and adjust the stop bolt. c. Tighten the jam nut on conventional knuckles from 65-85 lb-ft (68-101

N•m).

Four-Piece Steering 1/2 Inch Stop Bolt

1. Place washer onto adapter.

2. Apply adhesive patch material into the

3/4-inch knuckle bore stop screw adapter hole.

3. Install adapter with washer into threaded knuckle cavity.

4. Tighten adapter to 85-115 (115-155

N•m).

5. Start jam nut onto 1/2-inch bolt, and install bolt and jam nut assembly into adapter.

6. Place a 1/8-inch (3 mm) spacer between the stop bolt and the boss on the axle beam.

7. Turn the steering wheel until the boss on the axle beam touches the spacer in from of the stop bolt. Measure the turn angle.

8. If the maximum turn angle does not meet vehicle manufacturer's specifications, adjust the maximum turn angle. In a power steering system, adjust the pressure relief. In a manual steering system, follow guidelines and specifications form Blue Bird.

9. When the maximum turn angle is correct: a. Loosen stop bolt jam nut. Figure

68. b. Insert 1/8 inch spacer between the stop bolt and the axle beam boss with the steering arm in the full-turn position. c. Tighten the jam nut from 50-75 lb-ft

(68-101 N•m).


Next

Figure 68

Adjust the Pressure

Relief in the Power

Steering System (Setting the Maximum Turn

Angle)

The pressure relief in the power steering system stops or reduces forces applied to the axle when the wheel is moved in the fullturn position.

Check the pressure relief if the steering arm is damaged or the power steering gear is serviced.

Two types of systems are used to adjust the pressure relief:

• Mechanical Stop on the Pitman Arm or in the Assist Cylinder

• Hydraulic Pressure Relief in the Power

Steering Gear


Caution

Meritor does not recommend a power steering system that does not have mechanical stops or pressure relief before the maximum turn angle is obtained. The stops or the pressure relief are used to prevent damage to the axle.

Axles with Conventional

Wheel Ends

Mechanical Stop

Use the mechanical stop in the steering system to adjust the pressure relief. Do not use the stop bolt on the knuckle alone to adjust the poppet valve pressure relief.

Note

Refer to the specified procedures from Blue

Bird.

Caution

Use a pressure gauge to make sure t hat the pressure drops from the maximum system delivery pressure to a maximum of 700-1000 psi (4825-6890 kPa) BEFORE the full turning angle is achieved.

Steering systems with mechanical stops are adjusted when the wheels are turned to the full right and full left turn positions. The stop travel is set at 1/8 inch (3 m) before the top bolt contacts the axle beam boss.

Figure 69.

39


Next

Figure 69

Hydraulic Pressure

Relief in the Steering

Gear

Note

Refer to the specified procedure from Blue

Bird. The stop bolt should always have a minimum clearance of 1/8-inch (3 mm) between the stop bolt and the axle beam boss.

Hydraulic steering gears with poppet valves are adjusted with a spacer between the stop bolt in the knuckle and the boss on the axle beam. The poppet valves are adjusted to stop or reduce steering forces from t he 1/8inch (3 mm) specified distance between the beam boss and the spacer. Figure 70.

Figure 70

Turning Radius Angle

When turning, the inner wheel must turn at a greater angle than the outer wheel. This angle is the turning radius angle (often called the Ackerman angle). Figure 71.

Figure 71

The angle is built into the design of the tie rod arms, the tie rod ends and the cross tube assembly to give the best possible road


Next

contact and to minimize tire wear during turns.

Check the turning radius angle with the radius plates on the alignment equipment.

If the angle is not within specifications, premature tire wear will occur. Inspect the knuckle, tie rod arms, tie rod ends and cross tube for wear or damage. Service as necessary.

King Pin Inclination

King pin (or steering axis) inclination is the angle measured between the center line of the king pin and the vertical position (as viewed from the front of the vehicle).

Figure 72.

The king pin inclination and the camber angle are designed into the axle to place the tire tread center line in contact with the road.

This reduces steering effort and improves directional stability.

Use an alignment machine to check the king pin inclination angle.

The king pin inclination is not adjustable. If the inclination is not at the specified angle, check the axle beam and knuckle for damage. Service as necessary.

Camber Angle

Caution

Axle camber is not adjustable. Do not change the axle camber angle or bent the axle beam. Bending the axle beam to change the camber angle can damage the axle and reduce axle strength, and will void

Meritor's warranty. A bent axle beam can also cause a vehicle accident and serious personal injury.

Camber is the angle of the tire with respect to the ground. Camber is positive when the distance between the top of the wheels is greater than the distance at the ground.

Figure 73.

A small amount of positive camber is built into the knuckle because camber changes with load. This results in a zero camber angle when the vehicle is operated at the normal load.

If camber is out of specification by more than 1 1/2 degrees, rapid or uneven tire wear will occur. Bias ply tires will show excess camber easily, while with vehicles equipped with radial tires, excess camber will not be as evident.

Figure 72


Figure 73

The camber angle is not adjustable. The camber angle is machined into both the axle

41


Next

beam and the knuckle. If the camber angle is not at the specified angle, check the axle

Conditions

Camber angles machined into axles:

Hubs not installed.

Axles not installed in vehicle.

Load not applied on axle.

Old Camber Specification

Ales with Assembly Dates:

No Date indicated on tag

Prior to Aug 31, 1992 (92244)

Any date with a "P" Suffix

Left Side Right Side

+3/4°

Nominal beam and the steering knuckle for damage.

Service as necessary.

+1/4°

Nominal

New Camber Specification

Axles with Assembly Dates

On or after Sep 1, 1992

(92245) with no "P" suffix

Left and Right Sides

+1/4° Nominal

Camber angles of axles equipped with hubs

Camber angles under load

Axle installed in vehicle

+3/4°

(+7/16°) or

+1 3/16°to

5/16° (final reading)

+11/16° to -


+1/4°

(+7/16°) or

+11/16° to -


+3/16° to -


+1/4° (+7/16°) or

+11/16° to -3/16° (final reading)

+3/16° to -11/16° (final reading)

Table D - Camber Angle Recommendations

Use an alignment machine to check the camber angle. Refer to the procedure of the manufacturer of the alignment equipment.

The table above gives the specification

Meritor builds into the axle.

If caster is too much, steering effort will increase or may amplify a shimmy condition.

Caster Angle

Caster is the forward or rearward tilt of the king pin center line when viewed from the side of the vehicle. The caster angle is the angle from the vertical position to the center line of the king pin. If the top of the king pin axis is toward the rear of the vehicle, the caster is positive. A slight positive caster creates a self-aligning action that helps to stabilize the vehicle after turning and stabilizes it for driving straight ahead.

Figure 74.

Always use an alignment machine to check the caster angle. When checking caster, refer to the instructional procedures from the alignment equipment manufacturer.

Figure 74

The caster angle is controlled by tapered shims installed under the leaf springs.

Adjust caster according to Blue Bird specifications and procedures.


Next

Meritor recommends a caster setting of +1 degree to +2 1/2 degrees for vehicles with manual steering and +2 degrees to +4 1/2 degrees for vehicles with power steering.

Adjust the Toe-In

Toe is the relationship of the distance between the front of the front tires and the rear of the front tires.

When the front distance is less than the rear distance, the wheels are "toed in". Toe-in is designed into the vehicle to counteract the tendency of the tires to toe-out when the vehicle is driven.

Incorrect toe-in will result in rapid tire wear.

Toe-in specifications:

• Unloaded vehicles 1/16 inch (1.587 m)

+1/31 inch (0.794 mm)

• Loaded vehicles 1/32 inch (0.794 mm)

+1/32 inch (0.794 mm).

Caution

Most tire wear is caused by incorrect toe settings. Do not change camber or caster settings to correct tire wear problems. If the axle assembly is bent to change caster or camber, the strength of the axle is reduced and the warranty is voided. An axle damaged by bending may cause a vehicle accident and result in serious personal injury.

1. Make sure the vehicle is on a level surface. Place blocks behind the rear wheels to prevent the vehicle from moving. Raise the vehicle so that the front tires are off the floor.

Warning

Park the vehicle on a level surface. Block the wheels to prevent moving. Support the vehicle with safety stands. Do not work under a vehicle supported only by jacks.

Jacks can slip and fall over. Serious personal injury can result.

2. Use jacks to raise vehicle so that front tires are off the ground. Support the front axle with safety stands.

3. Use paint or chalk to mark the center area of both front tires around t he complete outer surface of the tire.

4. Place the pointers of a trammel bar on the marks of each tire. Rotate the tires.

Make sure a straight line is marked on the outer surface of the tire.

Note

Do not measure toe-in with the front axle in the raised position. The weight of the vehicle must be on the front axle when toe-in is measured.

5. Lower the vehicle to the floor. Move the vehicle forward and backward 10 feet (3 meters).

6. Place the trammel bar at the back of the tires. Raise the pointers so that the pointers are level with the spindles.

Align the pointers with the marks on the tires. Measure and record the distance between the pointers.

7. Place the trammel bar at the front of the tires. Raise the pointers so that the pointers are level with the spindles.

Align the pointers with the marks on the tires. Measure and record the distance between the pointers. Figure 75.

Figure 75


43


Next

8. To obtain the toe measurement, subtract the distance reading between the front of the tires from the distance reading between the back of the tires. Figure 76.

9. If the toe measurement is not at the specified distance, refer to the following procedure. a. Loosen the tube clamp nut and bolt on each end of the cross tube. b. Turn the cross tube until the specified toe-in distance is obtained. c. The threaded portion of the tie rod end must be installed into the cross tube beyond the point where the tube slot stops. d. Tighten the nut and bolt on each end of the cross tube to the specified torque.

10. Repeat Steps 1-8 to check the toe-in dimension.

Figure 76

Diagnostics

Warning


Front Non-Drive Steering Axle Diagnostic Chart

The following chart is for troubleshooting front non-drive steering axle conditions.

Condition Cause Correction

Tires wear out quickly or have uneven tire tread wear.

Vehicle is hard to steer.

1. Tires have incorrect air pressure.

2. Tires out of balance.

3. Incorrect tandem axle alignment.

4. Incorrect toe-in setting.

5. Incorrect steering arm geometry.

6. Excessive wheel end play exists.

1. Power steering system pressure low.

2. Steering gear linkage not assembled correctly.

3. Steering linkage needs lubrication.

4. King pins binding.

5. Incorrect steering arm geometry.

6. Caster out of adjustment.

7. Tie rod ends hard to move.

8. Worn thrust bearing.

1. Place specified air pressure in tires.

2. Balance or replace tires.

3. Align tandem axles.

4. Adjust toe-in specified setting.

5. Service steering system as necessary.

6. Readjust wheel bearings.

1. Repair power steering system.

2. Assemble steering gear correctly.

3. Lubricate steering linkage.

4. Replace king pins.

5. Service steering system as necessary.

6. Adjust caster as necessary.

7. Replace tie rod ends.

8. Replace thrust bearing.


Next

Tie rod ends are worn and require replacement.

1. Tie rod ends require lubrication.

2. Severe operating conditions.

3. Damaged boot on tie rod end.

1. Lubricate ends of cross tube. Make sure lubrication schedule is followed.

2. Increase frequency of inspection and lubrication intervals.

Bent or broken cross tube, tie rod end ball stud, steering arm or tie rod end.

(Component requires replacement.)

Worn or broken steering ball stud.

Worn king pins and king pin bushings.

1. Too much pressure in t he power steering, pressure exceeds OEM specification.

2. Power steering system cut-off pressure, out of adjustment.

3. Vehicle operated under severe conditions.

4. Add-on type of power steering system not installed correctly.

5. Steering gear overtravel poppets improperly set or malfunctioning.

6. Axle stops improperly set.

1. Drag link fasteners tightened higher than OEM specified.

2. Lack of lubrication or incorrect lubricant.

3. Power steering stops out-ofadjustment.

1. Worn or missing seals and gaskets.

1. Adjust power steering system to specified pressure.

2. Adjust power steering system to specified pressure.

3. Make sure vehicle is operated correctly.

4. Correctly install add-on power steering system.

5. Check for proper operation or adjust overtravel of poppets to

OEM specification.

6. Set axle stops to OEM specification.

1. Tighten drag link fasteners to specified torque.

2. Lubricate linkage with specified lubricant.

3. Adjust stops to specified dimension.

1. Replace seals and gaskets.

2. Lubricate axle with specified lubricant.

3. Lubricate axle at scheduled frequency.

4. Use correct lubrication procedures.

3. Axle not lubricated at scheduled frequency.

4. Incorrect lubrication procedures.

5. Lubrication schedule does not match operating conditions. schedule to match operating conditions.

Vibration or shimmy of front axle during operation.

2. Wheels and/or tires out-ofbalance.

3. Worn shock absorbers.

2. Balance or replace wheels and/or tires.

3. Replace shock absorbers.

Warning



45


Next

Group Number

2

3

Typical Vocations Vehicle Build

Fire and rescue, city delivery, inner city coach, heavy haul, school bus, motor home, transit coach

Logging, oil field, construction, heavy haul, yard tractor

(highway licensed), residential refuse

After July 1, 1996

Before July 1, 1996, use Group Number 3

Table E: Vocational Groups

Typical Operation

Conditions

Lower mileage operation (less than

50,000 miles/year (80

500 km/year)) operation (less than

25,000 miles/year

(40/250 km/year))

Lubrication, Inspection and Maintenance Schedule

Component

Tie Rod

Ends

Group 2

Group 3

Inspect the

Tie Rod

Assembly for

Movement

Group 2

Group 3

Tie Rod

End Shop

Inspection

Ball Stud on

Steering

Arms

Easy Steer

Plus™ Axle

Ball Studs

Sealed Axle

Ball Studs

Drag Link

King Pins and

Bushings

Steering

Arm Bolts

Thrust

Bearings

Service Intervals

48 hrs

5,000 miles/

100 hrs

First

6,000 miles of operation

8050 km

10 000 km

10,000 miles

16 100 km

20,000 miles

32 200 km

36,000 miles

58 000 km

I

I

40,000 miles

64 000 km

50,000 miles

80 500 km

100,000 miles

160 000 km

L*

I

I

L*

L*

L*

200,000 miles

320 000 km

I


Next

Steering

Knuckle

Vertical

End Play

Inspection

I

I

Upper and

Lower King

Pin

Bushings for Wear

I

I

Draw Key

Nuts

In-service vehicle

Sealed Hub

Unit

Inspection

T

T

I

I=Inspect

L=Lubricate

T=Tighten to Specifications.

*If power washers are used during vehicle cleaning operations, lubrication intervals need to be adjusted.

Frequent power washed vehicles will require more frequent lubrication.

Table F: Lubrication, Inspection and Maintenance Schedule

Component Greasing

Interval

Grease Meritor

Specification

NLGI

Grade

Grease Type Outside

Temperature

King Pins and

Bushings,

Thrust

Bearings, Ball

Studs on

Steering Arm,

Tie Rod Ends, and Drag Link

Truck Hub

Unit

100,000 miles (160

000 kilometers) or once a year, whichever comes first

No Lube to

Hub

Multi-

Purpose

Grease

Unit

Sealed for life of component

O-617-A

Or

O-617-B

1 or

2 lubricate

Lithium 12-

Hydroxystearate or Lithium

Complex

Refer to the grease manufacturer's specifications for the temperature service limits

Table G: Front Non-Driving Axle Greasing Intervals and Specifications


47


Next

On-Highway

Operation Intervals

Check

Oil

Level

1,000 miles

(1600 kilo meters)

Petroleum

Oil Change

Whichever comes first:

Seals replaced

Brakes relined

100,000 miles

(160 000 kilometers)

Once a year

Off-Highway

Operation Intervals

Check Oil

Level

1,000 miles

(1600 kilometers)

Petro- leum

Oil

Change

Whichever comes first:

Seals replaced

Brakes relined.

Once a year.

Meritor

Specs

O-76A,

Gear Oil

O-76D,

Gear Oil

O-76E,

Gear Oil

O-76J,

Gear Oil

Heavy

Duty

Engine

Oil

Heavy

Duty

Engine

Oil

Military

Specs

MIL-L-

2105-D

MIL-L-

2105-D

MIL-L-

2105-D

MIL-L-

2105-D

MIL-L-

2104-B,

C, D or E

MIL-L-

2104-B,

C, D or E

Oil

Description

GL-5, SAE

85W/140

GL-5, SAE

80W/90

GL-5, SAE

75W/90

GL-5, SAE

75W

API –CD,

CE, SF or

SG

SAE 40 or

50 (1)

API –CD,

CE, SF or

SG

SAE 30 (2)

Outside Temperature

F° C°

Min Max Min Max

10 None 12 None

-15 None -26 None

-40 None -40 None

-40 36 -40 2

10 None 12 None

-15 None -26 None

Table H: Wheel End Oil Change Intervals and Specifications

(1) Current designations are acceptable. Multi-weight engine oils are acceptable if the SAE rating ends in a 40 or 50.

(2) Current designations are acceptable. Multi-weight engine oils are acceptable if the SAE rating ends in a 30.

Lubrication

Tie Rod End Lubrication

This procedure refers to all tie rod ends on

Meritor non-drive steering axles.

1. Turn the vehicle wheels straight ahead.

Figure 77.

2. Wipe the zerk fitting clean with shop towels. Figure 78.

3. Wipe the seal/boot clean with shop towels.

4. Attach a grease gun to the zerk fitting.

Either a hand or air pressure grease gun is acceptable. If using air pressure, do not exceed 150 psi (1035 kPa). Figure

79.

5. Discolored old grease should come out of the purge holes near the boot crimp or bellows area (typically three or more places). Figure 80.

6. If the tie rod end is designed for lube service and it does not accept grease: a. Remove the zerk fitting. b. Inspect the threaded zerk fitting hole in the tie rod end and remove any obstructions. c. Install a new zerk fitting. d. Continue the lubrication procedure.

Note

Synthetic lubes are not yet approved for tie rod end lubrication.

purged from the boot.


Next

Figure 77

Figure 79

Figure 78


49


Next

King Pins

Straight King Pins

Note

This procedure applies to 901, 903, 910,

935, 952 and 970 front conventional axles.

Refer to the identification tag on the front of the axle beam.

Figure 80

On conventional front axles, the grease fittings are on the side of the knuckle.

Warning



Next

1. Lift the vehicle so that the tires are off the ground. The front tires should be off the ground when the king pins are lubricated. Support the vehicle with safety stands. Place blocks in front and behind the rear wheels to keep the vehicle from moving. Set the parking brake.

2. Lubricate the king pins through the top and the bottom king pin cap grease fittings. Figure 81.

3. Apply lubricant until new lubricant comes from between the upper shim pack and thrust bearing seal.

4. Lower the vehicle so that the wheels touch the ground.

5. Apply lubricant to the bottom fitting until new lubricant purges and fills the thrust bearing.

Figure 81

Ball Studs on Steering Arm, the Tie Rod Arm Ends and the Drag Link

1. Make sure the tires touch the ground.

DO NOT RAISE THE VEHICLE.

2. Clean off all grease fittings prior to lubrication.

3. Apply lubricant until new lubricant comes from the boot. Figure 81.

Figure 81

Grease-Lubricated

Wheel Bearings

Note

This procedure applies to hubs with greaselubricated wheel bearings.

1. Remove the tire and wheel assembly.

Remove and disassemble the hub. Refer to the section on "Wheel Ends".

2. Remove the old lubricant from all parts.

Discard the seals. Inspect the wheel bearings for wear or damage. Replace worn or damaged bearings. Refer to

"Preparing Parts for Assembly" section.

3. Force the specified lubricant from the large end of the cones into the cavities between the rollers and cage. Pack the hub between the bearing cups with lubricant to the level of the small diameter of the cups. Figure 82.


51


Next

Figure 82

4. Install the inner and outer bearing cones into the cups in the hubs. The bearing cups must be pressed tight against the shoulder in the hubs.

5. Install new wheel seals in the hubs.

6. Install the hub and the wheel and tire assembly. Install the outer wheel bearing cone in the hub. Install the adjusting nut.

7. Adjust the wheel bearings. Refer to

Section entitled "Check and Adjust the

Wheel Bearings".

Oil-Lubricated Wheel

Bearings

Note

This procedure applies to hubs with oillubricated wheel bearings.

Check the level on the cap. If the oil level is not at the specified level on the cap, remove the fill plug. Add the specified oil until the oil is at the specified level. Figure 83.

Figure 83

Inspection and

Maintenance

Inspection Tools

Before performing an inspection of axle components, make sure the proper tools are available. Using the proper tools will ensure safety and provide the most accurate results.

Check for the following tools:

• Dial Indicator

• Tire Blocks

• Jack

• Safety Stands

• Pry Bar

• Torque Wrench

Inspection

Caution

The repair or reconditioning of front axle components is not allowed. Meritor recommends replacing damaged or out-ofspecification components. All major components are heat treated and tempered.

The components cannot be bent, welded, heated or repaired in any way without reducing the strength or life of the component and voiding the warranty and


Next may cause a vehicle accident which can result in serious personal injury.

Check the following during an inspection.

Fasteners. Make sure all fasteners are tightened to the specified torque. Use a torque wrench to check the torque in a tightening direction. As soon as the fastener starts to move, record the torque. Correct if necessary. Replace any worn or damaged fasteners.

Wear and Damage. Inspect the parts of the axle for wear and damage. Look for bent or cracked parts. Replace all worn or damaged parts.

Pivot Points. Make sure looseness does not exist at the pivot points. Make sure the pivot points are lubricated.

Operation. Make sure all the parts move freely through the complete turning radius.

Tire Wear. Inspect the tires for wear patterns that indicate suspension damage or misalignment.

Steering Arm Bolts. Check torque on Easy

Steer Plus™ MFS 10-2015 and MFS 12-

2015 axles every 200,000 miles (320 000 km). Refer to the "Checking Steering Arm

Bolts" in this section.

Checking Draw Key Nuts

Tighten the draw key nuts from 30 to 45 lbft (41-61 N•m) at the following intervals.

Figure 84.

• After the first 6,000 miles (10 000 km) of new vehicle operation.

• Every 36,000 miles (58 000 km) of operation.


Figure 84

Checking Steering

Knuckle Vertical End

Play

1. Place blocks in front and behind the rear wheels to prevent the vehicle from moving.

Warning


2. Use a jack to raise the vehicle until the front wheels are off the ground. Support the front axle with safety stands.

3. Install a dial indicator so that the base is on the I-beam and that the tip is on the top knuckle cap. Figure 85.

4. Place a pry bar between the boss for the tie rod arm and the I-beam. Push the knuckle to the bottom of vertical travel.

Figure 86.

53


Next

Note

If one bushing requires replacement, then replace both bushings in the knuckle.

5. Set the dial indicator on "zero" (0).

6. Use the pry bar to push the knuckle upward. Record the reading on the dial indicator.

The reading must be 0.001- to 0.025inch (0.025-0.635 mm) for new or rebuilt axles and 0.001- to 0.065-inch

(0.025-1.650 mm) for axles in service.

Figure 86.

If the reading is "zero" (0), remove the knuckle and remove shims from the shim pack.

If the reading is more than the maximum specification, remove the knuckle and add shims to the shim pack.

Figure 85

Figure 86

Checking the Upper and

Lower King Pin Bushings for Wear

1. Place blocks in front and behind the rear wheels to prevent the vehicle from moving.

Warning


2. Use a jack to raise the vehicle until the wheels are off the ground. Support the vehicle with safety stands.

3. Check the upper king pin bushing for wear. Install a dial indicator so that the base is on the I-beam and that the tip is against the side of the top of the knuckle. Figure 87.

4. Set the dial indicator to "zero" (0).


Next

Note

If one bushing must be replaced, replace both bushings in the knuckle.

5. Move the top of the tire side-to-side towards and away from the vehicle. If the dial indicator moves a total of 0.010inch (0.254 mm), the upper bushing is worn or damaged. Replace both bushings. Figure 87.

Figure 87

6. Check the lower king pin bushing.

Install a dial indicator so that the base is on the I-beam and that the tip is against the side of the bottom of the knuckle.

Figure 88.


8. Move the bottom of the tire side-to-side towards and away from the vehicle. If the dial indicator moves a total of 0.010inch (0.2254 mm), the lower bushing is worn or damaged. Replace both bushings. Figure 88.


Figure 88

Inspect the Tie Rod Ends

1. Park the vehicle with the steering wheels in the straight-ahead position.

Figure 89.

Figure 89

55


Next

2. Place blocks in front and behind the rear wheels to prevent the vehicle from moving. Set the parking brake.

3. Remove dirt and grease from the tie rod end seals.

4. Place indicator base on the bottom of the tie rod arm.

5. Place the indicator tip near the ball stud center (grease fitting) of the tie rod end.

Figure 90.

Figure 90


Caution

Check the tie rod end play by hand. Do not use a pry bar. If a pry bar is used, readings from the dial indicator will not be accurate.

7. Move the tie rod and cross tube assembly up and down by hand.

8. Record the dial indicator reading. If the dial indicates a reading of more than

0.060-inch (1.52 mm), tie rod end replacement is required.

9. Place the dial indicator on the tie rod end assembly at the opposite side of vehicle and repeat Steps 1 through 8.

Inspect the Tie Rod

Assembly for Movement

This procedure applies to all tie rod assemblies.

To perform this inspection, the entire system must be "unloaded" (i.e., the front end of the vehicle must be raised and supported with stands).

Caution

Do not grease the tie rod assembly before performing the inspection. Doing so may provide inaccurate results.

Replace the entire tie rod end if the boot is torn or missing. Do not replace the boot only.

1. Place blocks in front of and behind the vehicle's rear wheels. Using the bottom of the I-beam or frame rails, raise the front end off the ground, and support with stands.

2. With the engine off, turn wheels from full left to full right, and then return to the straight-ahead position. (This step will require more force for vehicles with power steering turned off.)

3. Check that the boot is in place and completely installed over the tie rod end.

Note

The boot may be missing completely or may not completely cover the ball joint.

4. Check for cracking or tears in the boot.

Also, check the boot seals for damage.

Replace the entire rod end if the boot is damaged. Figure 91.


Next

Figure 91

Warning

A cotter pin must be installed through the tie rod end with the tie rod end nut tightened to torque specification to securely attach the tie rod. Loss of the cotter pin will allow the tie rod end nut to become loose and affect vehicle steering and possibly result in loss of steering control.

5. Check that the tie rod nut is installed and secured with a cotter pin. If the cotter pin is missing, check the nut torque specification and then install a new cotter pin. Always tighten tie rod nut to specified torque when setting the cotter pin.

Caution

The tie rod ends must be at the end of the cross tube slot to ensure adequate thread engagement.

6. Check that the tie rod end is threaded correctly into the cross tube and engaged deeper than the end of the cross tube slot. The tie rod end must be visible the entire length of the cross tube slot. Figure 92.


Figure 92

7. Check that zerk fittings are installed.

Replace a damaged zerk fitting with a new one. Some tie rod ends are nongreaseable and will not have zerk fittings. Do not install fitting if tie rod end is non-greaseable type.

Caution

Do not use the following items or methods to check for movement of the tie rod assembly.

Damage to components can result if:

• A crow bar, pickle fork or 2 x 4 is used.

• A tool instead of your hands is used to

grasp the cross tube assembly that results in cross tube damage.

• Pressure or force is applied to the ends

or the joints of the assembly.

• The tires are rocked either with the

vehicle on the ground or with the wheels raised.

8. By hand or using a pipe wrench with jaw protectors to avoid gouging the cross tube, rotate the cross tube toward the front of the vehicle and then toward the rear. After rotating, center the cross tube. If the cross tube will not rotate in either direction, replace both tie rod ends.

9. Position yourself directly below the ball stud socket. Using both hands, grab the assembly end as close to the socket as

57


Next

possible (no more than 6 inches or 152.4 mm). Apply hand pressure

(approximately 100 pounds) vertically

(up and down) in a push-and-pull motion several times. Check for any movement or looseness at both tie rod end locations.

10. If there is any movement in the tie rod assembly, replace both tie rod ends.

Tie Rod End Shop

Inspection

Caution

Replace the entire tie rod end if the boot is torn or missing. Do not replace the boot

only.

1. Check the tie rod boot for cracks, tears or other damage. All tie rod ends with a damaged boot require that the entire tie rod end be replaced. Figure 91.

2. Grab by hand (or using a pipe wrench with jaw protectors to avoid gouging the cross tube) and slightly rotate the cross tube toward the front of the vehicle and then slightly toward the rear. After this movement, check in both directions, centering the cross tube between the stop positions. If the cross tube will not rotate in either direction, replace both tie rod ends.

3. Position yourself directly below the ball stud socket. Using both hands, grab the end as close to the socket as possible (no more than 6 inches or 152.4 mm from the end). Firmly apply hand pressure

(approximately 100 pounds) in a vertical push and pull motion several times.

When moving the assembly, check for any movement at both tie rod ends.

Warning

If any movement is detected by hand, replace the worn components with new components before releasing the vehicle back into service.

4. If any movement is detected at one tie rod end, replace it and the other tie rod end. Always replace tie rod ends in pairs, even if only one tie rod is found damaged.

Warning

Do not attempt to straighten a bent cross tube. Damage to the axle can result. Be certain to replace any cross tube with an original equipment cross tube (with the same length, diameter and threads).

5. Inspect the cross tube and clamps for damage. Figure 93.

• Replace the cross tube if it is cracked or bent.

• Replace the clamps if they are damaged.

• Replace the entire cross tube assembly if either clamp is welded onto it.

Figure 93

6. Check for proper installation of the tie rod end clamp to the cross tube. Be certain that tie rod ends are threaded in the cross tube past the clamps and the slots at the cross tube ends.

7. Check that zerk fittings are installed.

Replace damaged zerk fittings. Replace damaged zerk fittings. Figure 94.

Refer to Table E.


Next

Some tie rod ends have no zerk fittings because they are not greaseable. Do not install a zerk fitting on a non-greaseable design tie rod end.

8. Check that the cotter pin is in place.

Replace if missing. Tighten the tie rod end nut to the specified torque and then insert the cotter pin through the castellated nut and the hole in the tie rod end.

Figure 94

Tie Rod Service Tips

If available, a service pit is recommended for tie rod inspection and maintenance. If a service pit is not available, use the following method.

1. Use jacks to raise the vehicle using the following. a. The vehicle must be on a level surface. b. Put blocks under the wheels not being raised to keep the vehicle from moving. c. Raise the vehicle so that the area to be serviced is off the ground.

Support the vehicle with safety stands. d. Inspect and lubricate the tie rod ends as specified in Table E.

2. Drive-on ramps may also be used.

Observe all of the manufacturer's safety recommendations.

Tie Rods

Effect of Tie Rod End Wear on

Steering Linkage

Unless tie rod end wear becomes excessive, a safe steering linkage is maintained.

However, tie rod end wear can affect uniform steering control and, ultimately, wear to the front tires.

Detecting Tie Rod End Wear During

Vehicle Operation

A driver may not always detect a loose tie rod end condition during vehicle travel conditions. This is why it is important to inspect tie rod ends for wear and allowable movement at regular intervals. Refer to

Table E for inspection intervals

Tie Rod End Wear

It is imperative that inspection and maintenance is performed at the recommended intervals to minimize the impact of tie rod end wear. Tie rod end wear occurs over time, under normal operating conditions. As wear occurs, the preload bearings inside each tie rod end provide less resistance. Excessive tie rod end wear will affect steering and contribute to premature wear of the tires and other axle components. Figure 95.


59


Next

Tighten the nuts that hold the draw keys on the side of the knuckle to 30-45 lb-ft (41-61

N•m) at the following times. Figure 96.

• After the first 6,000 miles (10 000 km) of new vehicle operation.

• Every 36,000 miles (58 000 km) of operation.

Figure 95

Tightening Draw Key

Nuts

Note

This procedure applies to all except 901,

903 and 970 Series axles. These axles do not utilize a draw key. Refer to the identification tag on the front of the axle beam.

Figure 96

Checking Steering Arm

Bolts

Warning

Take care when you use Loctite® to avoid serious personal injury. Follow the manufacturer's instructions to prevent irritation to the eyes and skin.

Note

This procedure applies to ALL axles included in this manual.

Check steering arm bolts for minimum 300 lb-ft (406 N•m) torque. If steering arm bolt torque has fallen below 300 lb-ft (406 N•m), remove bolts, clean all threads, and install new Loctite®. Tighten bolts from 300 to

450 lb-ft (406-610 N•m) torque. Check steering arm bolt torque every 200,000 miles

(320 000 km) or 24 months.


Next

Note

Old Loctite® must be removed from bolt threads and internal threads of knuckle itself. Reapply new Loctite® 680 (Meritor

#2297-K-5523).

Torque Specifications

Warning


Front Non-Drive Axles with Conventional Wheel Ends


Figure 97

61


Next

Front Axle with Conventional Wheel Ends Torque

Specifications

Item Description

1

2

3

4

5

6

7

8

9

10

Steering Arm to Drag Link Nut

Knuckle Cap Screw

Steering Arm to Knuckle Nut

Draw Key Nut

3/4" Stop Screw Adapter

1/2" Stop Screw Lock/Jam Nut

3/4" Stop Screw Lock/Jam Nut

Tie Rod Arm to Tie Rod End Nut

Cross Tube Clamp Nut

Tie Rod Arm to Knuckle Nut

Size

Torque Range lb—ft N•m

5/8"—16 60—115 82—155

5/8"—18 60—115 92—155

3/4"—16 90—170 123—230

7/8"—14 160—300 217—407

5/16"—18 20—30 28—40

7/8"—14 250—450 339—610

1"—14 390—725 529—982

1-1/8"—12 550—1025 746—1389

1-1/4"—12 775—1450 1051—1965

1-1/2"—12 1350—2525 1831—3423

7/16"—20

30—45

65—115

50—75

41—61

88—155

68—101

65—85 88—115

7/8"—14 160—300 217—406

1"—14 250—450 339—610

1-1/8"—12 350—650 475—881

1-1/4"—12 500—675 678—915

5/8"—11 40—60 55—81

3/4"—10 155—175 211—237

7/8"—14 250—450 339—610

1"—14 390—725 529—982

1-1/8"—12 550—1025 746—1389

1-1/4"—12 775—1450 1051—1965

1-1/2"—12 1350—2525 1831—3423

Table I—Front Axle with Conventional Wheel Ends


Next

Special Tools

Description Kent-Moore Owatonna Tool

Tool Number

(1)

Number (2)

King Pin Remover 4240

King Pin Bushing

Service Kit

Basic Service Kit

FF- and FG- Series

Kits

FL-Series Kit

(4)

PT 4375-A

PT 4370-10

PT 4370-20

Snap-On® Tool

Number (3)

References

4240 20 Ton:

CG430HYB

"Disassembly"

Section

"Disassembly"

Section

Table J—Special Tools

(1) Order Kent-Moore tools from: Kent-Moore, 28635 Mound Road, Warrren, MI 48092

(2)

Order Owatonna tools from: OTC Tool and Equipment Division, 655 Eisenhower Drive, Owatonna,

MN 55060

(3) See your local Snap-On® dealer.

(4)

Use Basic Service Kit along with the correct axle series kit

.

Back to Top


63

No results