Runout Tests

Tire and Wheel Runout

NOTE: Perform runout checks only after the vehicle has been driven far enough to warm the tires and to avoid false readings caused by temporary flat spots on the tires. Excessive radial and lateral runout of a wheel and tire assembly can cause roughness, vibration, wheel tramp, tire wear, and steering wheel tremor.





The extent of the runout is measured with Radial Runout Gauge. All measurements are made on the vehicle with the tires inflated to recommended inflation pressures.

Measure the (1) radial and the (2) lateral wheel runout at the positions shown in the illustration.

Use Radial Runout Gauge to measure the (4) radial runout of the tire at the center and outside ribs of the tread face and the (3) lateral runout on the tire sidewall as shown in the illustration. Mark the high points of radial runout for future reference.

Match Mounting Tires
Match mounting is a technique used to reduce radial runout. Excessive runout is a source of vibration, shimmy and poor handling concerns. Use the following steps to reduce radial runout:
1. Mark the wheel at the same point as the mark previously made when measuring the tire runout.
2. Dismount the tire and remount it 180° on the wheel so the original mark on the tire is opposite the mark on the wheel.
3. Inflate the tire to specification.
4. Measure the radial runout with Radial Runout Gauge at the center of the tread face. If the radial runout is reduced to acceptable guidelines, the tire can be used. If the radial runout remains excessive, check the wheel runout.