Rotation is advisable:
(1) If tires are highway type tread design:
Front (Steering) Axle - When required, replace tire when tire thread is worn to 1/8 inch (3.175 mm) or less. Rotate worn
tires to any other position. Retreaded or recapped tires are not to be used on steering axles.
Rear and Trailer Axles - Tires must be removed when thread is worn to no less than 1/16 inch (1.588 mm). However, tires
identified by the word "regroovable" molded on the side wall can be regrooved.
(2) If rib or highway type tire is used on front axle and lug or off-road type on rear axle positions:
Front (Steering Axle) -- Install new tires at front wheels when thread is worn to 1/8 inch (3.175 mm) or less.
Rear and Trailer Axles - Tires must be removed when the thread is worn to 1/16 inch (1.588 mm) or less. Tires
identified with the word "regroovable" molded on the sidewall can be regrooved.
3-17.7 Wheel and Tire Balancing. Out-of-round or out-of-balance wheels or tires can cause vehicle vibration, bounce and
shimmy. Wheels should be replaced if damaged or out-of-round. Out-of-round tires can usually be "trued" by a tire
checker. The tire and wheel assembly shiould then be dynamically balanced. Dynamic balances both statically and
dynamically, static balancing only balances statically.
3-17.8 Wear. Radial tires can exhibit three types of normal wear patterns: 1 Even, 2 Erosion, 3 Shoulder.
Even Wear like a bias tire, radial tires which have an even wear pattern is a sign that is being properly used and
Figure 3-3. Circumferential Tread Channeling