Jeep 1996 Grand Cherokee Service Manual - page 1340
TIRE AND WHEEL RUNOUT
Radial runout is the difference between the high
and low points on the tire or wheel (Fig. 2).
Lateral runout is the wobble of the tire or wheel.
Radial runout of more than 1.5 mm (.060 inch)
measured at the center line of the tread may cause
the vehicle to shake.
Lateral runout of more than 2.0 mm (.080 inch)
measured near the shoulder of the tire may cause the
vehicle to shake.
Sometimes radial runout can be reduced. Relocate
the wheel and tire assembly on the mounting studs
(See Method 1). If this does not reduce runout to an
acceptable level, the tire can be rotated on the wheel.
(See Method 2).
METHOD 1 (RELOCATE WHEEL ON HUB)
Check accuracy of the wheel mounting surface;
adjust wheel bearings.
Drive vehicle a short distance to eliminate tire flat
spotting from a parked position.
Make sure all wheel nuts are properly torqued.
Relocate wheel on the mounting, two studs over
from the original position.
Re-tighten
wheel
nuts
until
all
are
properly
torqued, to eliminate brake distortion.
Check radial runout. If still excessive, mark tire
sidewall, wheel, and stud at point of maximum
runout and proceed to Method 2.
METHOD 2 (RELOCATE TIRE ON WHEEL)
Rotating tire on wheel is particularly effective
when there is runout in both tire and wheel.
Remove tire from wheel and re-mount wheel on
hub in former position.
Check wheel radial runout (Fig. 3).
NOTE: If the vehicle is equipped with aluminum or
full faced wheels the tire must be removed to check
radial runout.
• STEEL WHEELS: Radial runout 0.040 in., Lat-
eral runout 0.045 in.
• ALUMINUM WHEELS: Radial runout 0.030 in.,
Lateral runout 0.035 in.
If point of greatest runout is near original chalk
mark, remount tire 180 degrees. Recheck runout.
SERVICE PROCEDURES
WHEEL INSTALLATION
The wheel studs and nuts are designed for specific
applications. They must be replaced with equivalent
parts. Do not use replacement parts of lesser quality
or a substitute design. All aluminum and some steel
wheels have wheel stud nuts which feature an
enlarged nose. This enlarged nose is necessary to
ensure proper retention of the aluminum wheels.
NOTE: Do not use chrome plated lug nuts with
chrome plated wheels.
Before installing the wheel, be sure to remove any build
up of corrosion on the wheel mounting surfaces. Ensure
wheels are installed with good metal-to-metal contact.
Improper installation could cause loosening of wheel nuts.
This could affect the safety and handling of your vehicle.
To install the wheel, first position it properly on the
mounting surface. All wheel nuts should then be tightened
just snug. Gradually tighten them in sequence to the
Fig. 2 Checking Tire Runout
Fig. 3 Checking Wheel Runout
ZJ
TIRES AND WHEELS
22 - 9
DIAGNOSIS AND TESTING (Continued)