Diagnosis Of Wheel Bearings - GMC 1986 P-Truck Service Manual

DIAGNOSIS OF FRONT SUSPENSION (CONT.)
PROBLEM
Noise In The Front
End
Wheel Tramp
Excessive or Uneven
Tire Wear
Scuffed Tires
Cupped Tires

DIAGNOSIS OF WHEEL BEARINGS

When diagnosing bearing condition, keep in mind
the general condition of all parts during disassembly
and inspection. Use Figures 1, 2, 3 and 4 to classify
POSSIBLE CAUSE
1. Ball joints and steering linkage need
lubrication.
2. Loose shock absorber or worn bush­
ings.
3. Worn control arm bushings.
4. Worn or loose wheel bearings.
5. Loose stabilizer bar.
6. Loose wheel nuts.
7. Spring is improperly positioned.
8. Loose suspension bolts.
1. Tire and the wheel are out of balance.
2. Tire and the wheel are out of round.
3. Blister or bump on the tire.
4. Improper shock absorber action.
1. Underinflated or overinflated tires.
2. Improper toe-in.
3. Wheels are out of balance.
4. Hard driving.
5. Overloading the vehicle.
1. Toe-in is incorrect.
2. Excessive speed on turns.
3. Tires are improperly inflated.
4. Suspension arm is bent or twisted.
1. Front shock absorbers are defective.
2. Worn ball joints.
3. Wheel bearings are incorrectly ad­
justed or worn.
4. Wheel and tire is out of balance.
5. Excessive tire or wheel runout.
FRONT SUSPENSION 3C-3
CORRECTION
1. Lubricate at the recommended inter­
vals.
2. Tighten the bolts or replace the
shock absorber.
3. Replace the bushings.
4. Adjust or replace the wheel bearings.
5. Tighten all the stabilizer bar attach­
ments.
6. Tighten the wheel nuts.
7. Reposition the spring.
8. Tighten to specifications or replace.
1. Balance the wheels.
2. Replace the tire.
3. Replace the tire.
4. Replace the shock absorber.
1. Inflate the tire to the recommended
pressure.
2. Adjust toe-in setting.
3. Balance the wheels.
4. Follow proper driving techniques.
5. Do not exceed the maximum recom­
mended payload rating.
1. Adjust toe-in setting.
2. Follow proper driving techniques.
3. Inflate the tires to the recommended
pressure.
4. Replace the suspension arm.
1. Replace the shock absorbers.
2. Replace the ball joints.
3. Adjust or replace the wheel bearings
(also replace the races).
4. Balance the wheel and tire.
5. Check and compensate for runout.
the failure, and follow the recommended repair proce-
dures.