Diagnosing Tire and Wheel Concerns

Felt in the steering wheel starting at 55 to 70 mph — front wheel balance issue. Rebalance. Felt in the seat — rear balance. If vibration persists after balancing — check for a bent wheel by spinning it on the balancer and watching for runout. Check for a tire with a shifted belt — a flat spot or bulge in the tread that makes the tire out of round.

Check tire pressures first — always. A 5 PSI difference side to side causes a noticeable pull. If pressures are equal, check alignment. If alignment is correct, swap the two front tires side to side. If the pull reverses direction — a tire is causing the pull from internal belt shift. If the pull stays — it is mechanical.

Center wear — overinflation. Both shoulder wear — underinflation. One-sided wear — camber problem, inspect ball joints and strut mounts. Feathering or sawtooth — toe alignment, check tie rods. Cupping or scalloping — worn shocks or struts. Tire wear patterns tell you what is wrong before you put the vehicle on a rack. Learn to read them from the parking lot.