Pontiac Fiero 1988 Service Manual page 156

SEALED WHEEL BEARING DIAGNOSIS
A W H E E L B E A R I N G A S S E M B L Y !
i N O I S E D I A G N O S I S I
W H E E L B E A R I N G A S S E M B L Y
L O O S E N E S S D I A G N O S I S
j
If i Road Tttt indicates notte. it could be wheels, bearings or tires, check the following.
1. Check lifts for proper prttiuri and uneven wear.
2. Raise car on a hoist md spin wheels; check for out-of-round tires, out-of-balance
tiros, bent rims, loo3© end/or rough wh©sl bssrings.
I "
1
S U S P E C T
BEARING)
NOISE
I
F R O N T W H E E L
B E A R I N G ASSEMBLY;]
I
O T H E R NOISE U
( C O R R E C T A S R E Q U I R E D ) !
Mount dial indicator as shown below.
Grasp bearing flange and, using a push-pull
movement, note the indicator readings.
R E A R W H E E L
B E A R I N G A S S E M B L Y
If looseness exceeds .1270 mm
(.005"). Replace hub and
bearing assembly.
Free the shoes from the disc, or remove calipers.
Reinstall 2 wheel nuts to secure disc to bearing.
Mount dial indicator as shown below.
Grasp disc and use a push-puM movement.
If looseness exceeds .1270 mm
(.005"). Replace hub and
bearing assembly.
Hoist Car and
Support Lower Control
end Spin Wheal with Engine.
CAUT80N: On front wheel drive cars drive wheel spin
should be limited to 35 MPH as indicated on the
speedometer. This limit is necessary because the
speedometer only indicates one-half on the actual wheel
speed when one drive wheel is spinning and the other
drive wheel is stopped. Unless care is taken in limiting
drive wheel spin, the spinning wheel can reach excessive
speeds. This can result in possible tire disintegration or
differontcal failure, which could cause serious personal
injury or extensive car damage.
Hoist Car Spin
Wheel with Wheel Spinner
NOISE OR R O U G H N E S S CAN f
j E J H g A R l D F R O M P R I V E R ' S S E A T |
NOISE OR R O U G H N E S S CAN
BE H E A R D F R O M D R I V E R ' S SE ATI
I Replace Hub and Bearing Assembly I
NOISE OR R O U G H N E S S
CANNOT B E H E A R D
I
No is® is not Wheal
Bearing Atttmlbly
J - 8 0 0 1
E X A M P L E O F MOUNTING
D I A L INDICATOR DRUM B R A K E S
E X A M P L E O F MOUNTING
D I A L INDICATOR DISC B R A K E S