Tires. Midland Belly/Bottom Dump Trailer 4.6MB, Belly/Bottom Dump Trailer

4.10.3 TIRES

When operating the trailer, it is the responsibility of the driver to check the tires frequently. Inflation pressures, wear patterns and matching are critical parameters that must be monitored. The following factors affect tire care:

1. Inspection frequency: Tires should always be checked before the start of a run and twice during the day or every 4 operating hours, whichever comes first. It is also a good practice to check the tires at each rest period during the day. When a driver hears unusual noise or experiences unusual handling characteristics, the first item to check is the tires. Problems found early, during frequent tire checks, can save more serious problems later on. A sampling of typical abnormal wear patterns are shown in the

Maintenance section along with their causes.

Always correct the cause of the tire wear problem before proceeding.

2. Inflation pressure: Tires should always be operated at their specified pressures. At their specified pressures, the tire is designed to run with the full width of the tread flat on the contact surface. Operating at other than specified pressures will change the tread

contact patterns and can dramatically shorten tire life. In addition, the tires will run hotter and can lead to blow-outs.

Check tire pressure when the tire is cold. A hot tire can read as much as 20 psi higher than a cold tire. If tires are over-inflated, check for poor load distribution, uneven surface contact, over-loading or poor operating conditions.

3. Tire matching: Do not mix ply types on the same axle. Their operating characteristics are different and will lead to uneven tire loading, rapid tire wear and adverse handling characteristics.

Matching also includes combining tires that have the same amount of tread remaining. A tire with more tread has a larger rolling radius and will have to carry a higher load. The best performance will be obtained when the rolling radius is within

1/8" for all tires on an axle.

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