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Wheels & Tires

WHEELS

Torque Requirements
It is extremely important to apply and maintain proper wheel mounting torque on your trailer axles. Torque is a measure of the amount of tightening applied to a fastener (nut or bolt) and is expressed as length times force. For example, a force of 90 pounds applied at the end of a wrench one foot long will yield 90 lbs.-ft. of torque. Using a torque wrench is the best method to assure the proper amount of torque is being applied to a fastener.

Note: Wheel lug bolts and lug nuts must be applied and maintained at the proper torque levels to prevent loose wheels, broken studs, and possible dangerous separation of wheels from axles.

Tightening Wheel Nuts

  1. Start all nuts by hand to prevent cross threading.
  2. Tighten nuts in an alternating/opposing sequence.
  3. The tightening of the fasteners should be done in stages. Following the recommended sequence, tighten fasteners per the following wheel torque chart.
  4. Wheel nuts should be torqued before first road use and after each wheel removal. Check and re-torque after the first 10 miles, 25 miles, and again at 50 miles. Check periodically thereafter.

Wheel Nut Torque Requirements

1st Stage 2nd Stage 3rd Stage
25-35 lbs.- ft. 50-65 lbs.-ft. 85 lbs.-ft.

 

TIRES

Before mounting tires onto wheels, make certain that the rim size and contour is approved for the tire as shown in the Tire and Rim Association Yearbook or the tire manufacturers catalog. Also make sure the tire will carry the rated load. If the load is not equal on all tires due to trailer weight distribution, use the tire rated for the heaviest wheel position.

Note: The capacity rating molded into the sidewall of the tire is not always the proper rating for the tire if used in a trailer application. Use the following guideline:
  • LT and ST tires: Use the capacity rating molded into the tire.
  • Passenger Car Tires: Use the capacity rating molded into the tire sidewall divided by 1.10.

Tire inflation pressure is the most important factor in tire life. Inflation pressure should be as recommended by the manufacturer for the load. Pressure should be checked cold before operation. Do not bleed air from tires when they are hot. Check inflation pressure weekly during use to insure the maximum tire life and tread wear.


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