DokterBan E-Newsletter

If the tires are wearing evenly there is no need to rotate the tires on a vehicle. If irregular wear becomes apparent or if the wear rate on the tires is perceptively different (from axle to axle for drive tires and side to side for steer tires), then the tires should be rotated in such a manner as to alleviate the condition.

Irregular or uneven tire treadwear patterns may be arrested and/or reversed by proper rotation of the tire to another vehicle wheel position (and possibly reversing the direction of rotation). This is particularly true of free rolling wheel positions such as steer and trailer tires. In fact, periodic rotation of steer tires can actually prevent – or at least delay – the onset of irregular wear. It is recommended that tires be rotated at about 50% of their expected service life.

When possible, tires should be moved to another axle on the vehicle, run in the opposite direction of rotation, and exchanged “inner-outer” if in dual mounting. There are no restrictions on criss-cross rotation. Trailer tire rotation should be the same as the drive tires.

In most applications, right front tires wear more slowly than the left fronts and are more susceptible to irregular wear conditions that can cause early removal due to steering system play. To extend steer tire life, closely monitor these tires and, should you see a visible difference in tread depth between them or an irregular wear pattern beginning to develop, switch the tires side to side. Steer tires that have developed objectionable irregular wear patterns should be rotated to the drive or trailer axles to use the remaining usable tread there.

On tandem drive axles the tires on the rear axle will wear faster than the tires on the front drive axle. To even out tire wear on all eight drive tires, extend tire mileage, and prevent having to replace the rear tires well before the forward drive tires are ready for removal, rotate the rear drive tires to the front axle and the front drive tires to the rear axle. (Many people use an X pattern for rotation and move the left rears to the right forward drive position and the right rears to the left forward position.) Since tire wear rates and wear uniformity also vary with wheel position, it may be desirable to put the inside tires on the outside and the outside tires on the inside too. This rotation should be done when the difference in tread depth between the forward and rear drive tires is between 3 and 4/32nds. Rotating tires at this point will also prevent excessive slip, loss of traction, and differential fight due to mismatched tire diameters between the axles and eliminate some wear and tear on the driveline.
(TRIB)