GMC Chevrolet Camaro 1998 Service Manual page 75

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General Information
Measuring Tire/Wheel Assembly Runout
If the vehicle has been sitting in one place for an
extended period of time, the tires may develop
flat spots at the point where the tires were resting on
the ground. These flat spots will affect the runout
readings. In order to eliminate these flat spots, drive
the vehicle long enough to warm up the tires. The flat
spots must be eliminated prior to taking any runout
measurements.
Measurement Procedure
1. Raise and suitably support the vehicle. Refer to
Lifting and Jacking the Vehicle
2. Obtain an initial indication of how much runout
exists:
2.1 . Spin the each tire and wheel assembly on
the vehicle by hand ( or at a slow speed
using the engine to run the drive wheels).
2.2. Visually inspect the amount of runout from
the front or rear of the tire.
3. Matchmark the each of the tire and wheel
assemblies in relation to the wheel studs and to
their position on the vehicle (LF, LR, RF, RR)
for future reference.
4. Remove the tire and wheel assemblies one at a
time and mount on a spin-type wheel balancer.
Refer to Wheel Removal
Locate the tire and wheel assembly on the
balancer with a cone through the.back side of the
center pilot hole.
Vibration Diagnosis and Correction 0-63
5. Wrap the outer circumference of tires that use
an all-season or aggressive tread pattern with
tape (1 ), in order to accurately measure the
radial runout.
6. Measure the tire and wheel assembly radial
runout.
176957
6.1. Slowly rotate the tire and wheel assembly
one complete revolution and ZERO the dial
indicator on the low spot.
6.2. Rotate the assembly one more complete
revolution and note the total amount of
runout indicated.
Maximum Radial Runout
• Measured off-vehicle: 1.27 mm (0.050 in)
• Measured on-vehicle: 1.52 mm (0.060 in)