If the tyres are wearing evenly there is no need to rotate the tyres on a machine. If irregular wear becomes apparent or if the wear rate on the tyres is perceptively different (from axle to axle for drive tyres and side to side for steer tyres), then the tyres should be rotated in such a manner as to alleviate the condition. Irregular or uneven tyre treadwear patterns may be arrested and/or reversed by proper rotation of the tyre 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 tyres. In fact, periodic rotation of steer tyres can actually prevent – or at least delay – the onset of irregular wear. It is recommended that tyres be rotated at about 50% of their expected service life.
When possible, tyres 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 tyre rotation should be the same as the drive tyres. In most applications, right front tyres 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 tyre life, closely monitor these tyres and, should you see a visible difference in tread depth between them or an irregular wear pattern beginning to develop, switch the tyres side to side. On tandem drive axles the tyres on the rear axle will wear faster than the tyres on the front drive axle. To even out tyre wear on all axles drive tyres, extend tyre mileage, and prevent having to replace the rear tyres well before the forward drive tyres are ready for removal, rotate the rear drive tyres to the front axle and the front drive tyres 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).
When possible, tyres 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 tyre rotation should be the same as the drive tyres. In most applications, right front tyres 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 tyre life, closely monitor these tyres and, should you see a visible difference in tread depth between them or an irregular wear pattern beginning to develop, switch the tyres side to side. On tandem drive axles the tyres on the rear axle will wear faster than the tyres on the front drive axle. To even out tyre wear on all axles drive tyres, extend tyre mileage, and prevent having to replace the rear tyres well before the forward drive tyres are ready for removal, rotate the rear drive tyres to the front axle and the front drive tyres 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).
- Devesh Dabas
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