GMC 4000 Series Service Manual page 495

Sec. 9A
Page 484
MECHANICAL STEERING
to multiple connector under dash.
9. Secure trailer hand brake control to column
if previously removed.
MECHANICAL STEERING TROUBLE DIAGNOSIS CHART
PROBLEM - STEERING WANDERS
CAUSE 1. Toe-in out of adjustment, or tie rod ends worn. Toe-out causes steering to wander.
2. Steering system out of alignment.
3. T ires badly worn, edge of tires are rounded off.
4. All steering components worn and loose.
5. Lack of lubrication in linkage and king pins.
REPAIR 1. Replace tie rod ends if worn, adjust to correct toe-in, and inspect steering arm and
tie rod for bent condition.
2. Align steering complete, caster, camber, and toe-in. Inspect spring components for
condition and wear.
3. Install new tires, and check alignment; abnormal tire wear indicates improper
alignment.
4. Replace or adjust loose or worn parts as necessary.
5. Lubricate as described in LUBRICATION (SEC. 0) of this manual. Free up any com­
ponents which are frozen and will not take lubrication.
PROBLEM - STEERING PULLS TO LEFT OR RIGHT
CAUSE 1. Camber incorrectly adjusted. Steering will generally pull to side of axle having
greatest positive camber.
2. Low air pressure in right or left tire. Steering will pull to side having low air
pressure.
3. Axle loose and shifted at spring U-bolts.
4. Rear axle loose at spring U-bolts if shifted at one side will cause steering to pull.
REPAIR 1. Adjust camber to correct specifications.
2. Inflate tire to correct pressure, check for air leak.
3. Align axle, and tighten U-bolt nuts to proper torque. Inspect for damaged parts.
4. Align rear axle and replace defective parts, if any. Tighten U-bolts to proper torque.
PROBLEM - HARD STEERING
CAUSE 1. Lack of lubrication - frozen king pins or ball joints.
2. Tire pressure too low.
3. Improper or excessive positive caster.
4. Steering gear adjusted too tight, or binding condition in steering column.
REPAIR 1. Lubricate, and free up king pins. Make certain all fittings take lubricant properly.
2. Inflate tires to proper pressure.
3. Adjust caster to correct specification as described in ''FRONT END ALIGNMENT''
(SEC. 3A) of this manual.
4. Adjust steering gear as described previously in this section. Adjust steering column
mounting clamps, and stop clamp as previously described in this section.
G M C S E R V I C E M A N U A L
looseness, or chucking and make adjustments, if
necessary. Check turn lights and horn operation.
10. Test action of steering wheel for bind,