WARNING: REPLACEMENT WITH USED WHEELS
IS NOT RECOMMENDED. THE SERVICE HISTORY
OF THE RIM MAY HAVE INCLUDED SEVERE TREAT-
MENT OR VERY HIGH MILEAGE. THE RIM COULD
FAIL WITHOUT WARNING.
TIRE AND WHEEL RUNOUT
NOTE: Runout should always be measured off the
vehicle and on a suitable balance machine.
Radial run out is the difference between the high
and low points on the outer edge of the tire or wheel.
Lateral run out is the total side±to±side wobble of
the tire or wheel.
Radial run out of more than 0.762 mm (.030 inch)
measured at the center line of the tread may cause
the vehicle to shake.
Lateral run out of more than 0.762 mm (.030 inch)
measured at the side of the tire as close to the tread
as possible may cause the vehicle to shake.
Sometimes radial run out can be reduced by relo-
cating the wheel and tire on the wheel studs (See
Method 1). If this does not reduce run out 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.
Verify all wheel nuts are properly torqued (Fig. 2).
Use run out gauge D-128-TR to determine run out
(Fig. 3).
Relocate the wheel on the mounting studs, two
studs over from the original position.
Retighten wheel nuts until all are properly
torqued. This will prevent brake distortion.Check radial run out. If still excessive, mark tire
sidewall, wheel, and stud at point of maximum run
out (Fig. 4) and proceed to Method 2.
METHOD 2 (RELOCATE TIRE ON WHEEL)
Rotating tire on wheel is particularly effective
when there is run out in both tire and wheel.
Remove tire from wheel and remount wheel on hub
in former position.
Check the radial run out of the wheel (Fig. 5). The
radial run out should be no more than 0.5 mm (0.020
inch) for steel wheels and 0.38 mm (0.015 inch) for
cast aluminum wheels.
Check the lateral run out of the wheel (Fig. 6). The
lateral runout should be no more than 0.8 mm (0.032
inch).
If the point of greatest wheel radial run out is near
the original chalk mark, remount the tire on the rim
180 degrees from its original position. Recheck the
run out. If this does not reduce the run out to an
acceptable level, replace the wheel and/or the tire.
Fig. 2 Tightening Wheel Nuts
Fig. 3 Run Out Gauge
Fig. 4 Chalk Marking On Wheel, Tire And Stud
22 - 10 TIRES AND WHEELSNS
DIAGNOSIS AND TESTING (Continued)
