Suspension And Steering - Jeep cherokee 1989 Owner's Manual

piston or damage.
5 Brake pad to rotor adjustment needed. lnspect automatic adjusting
mechanism for proper operation.
6 Scored or out of round rotor.
7 Loose caliper mounting bolts.
8 lncorrect wheel bearing adjustment.
67 Noise (high-pitched squeal)
1 Front brake pads worn out. This noise comes from the wear sensor
rubbing against the disc. Replace pads with new ones immediately!
2 Glazed or contaminated pads.
3 Dirty or scored rotor.
4
Bent support plate.
68 Excessive brake pedel travel
1 Partial brake system failure. lnspect entire system (Chapter 1
correct as required.
2 Insufficient fluid in master cylinder. Check (Chapter 1) and add
fluid bleed system if necessary.
3 Air in system. Bleed system.
4 Excessive lateral rotor play.
5 Brakes out of adjustment. Check the operation of the automatic
adjusters.
6 Defective proportioning valve. Replace valve and bleed system.
69 Brake pedal feels spongy when depressed
Air in brake lines. Bleed the brake system.
1
2 Deteriorated rubber brake hoses. lnspect all system hoses and lines.
Replace parts as necessary.
3 Master cylinder mounting nuts loose. lnspect master cylinder bolts
(nuts) and tighten them securely.
4
Master cylinder faulty.
5 lncorrect shoe or pad clearance.
6 Defective check valve. Replace valve and bleed system.
7 Clogged reservoir cap vent hole.
8 Deformed rubber brake lines.
9 Soft or swollen caliper seals.
1 0 Poor quality brake fluid. Bleed entire system and fill with new ap-
proved fluid.
70 Excessive effort required t o stop vehicle
1 Power brake booster not operating properly.
2 Excessively worn linings or pads. Check and replace if necessary.
One or more caliper pistons seized or sticking. lnspect and rebuild
3
as required.
Brake pads or linings contaminated with oil or grease, lnspect and
4
replace as required.
5 New pads or linings installed and not yet seated. It'll take a while
for the new material t o seat against the rotor or drum.
6 Worn or damaged master cylinder or caliper assemblies. Check par-
ticularly for frozen pistons.
Also see causes listed under Section 69.
7
71 Pedal travels t o the floor with little resistance
Little or no fluid in the master cylinder reservoir caused by leaking
caliper piston(s) or loose, damaged or disconnected brake lines. lnspect
entire system and repair as necessary.
72 Brake pedal pulsates during brake application
1 Wheel bearings damaged, worn or out of adjustment (Chapter 1
The Motor Manual Guy
Troubleshooting
2 Caliper not sliding properly due to improper installation or obstruc-
tions. Remove and inspect.
3 Rotor not within specifications. Remove the rotor and check for
excessive lateral runout and parallelism. Have the rotors resurfaced
or replace them with new ones. Also make sure that all rotors are the
same thickness.
4 Out of round rear brake drums. Remove the drums and have them
turned or replace them with new ones.
73 Brakes drag (indicated by sluggish engine performance
or wheels being very hot after driving)
1 Output rod adjustment incorrect at the brake pedal.
2 Obstructed master cylinder compensator. Disassemble master
cylinder and clean.
3 Master cylinder piston seized in bore. Overhaul master cylinder.
4 Caliper assembly in need of overhaul.
5 Brake pads or shoes worn out.
6 Piston cups in master cylinder or caliper assembly deformed. Over-
and
haul master cylinder.
7 Rotor not within specifications (Section 72).
8
Parking brake assembly will not release.
9 Clogged brake lines.
1 0 Wheel bearings out of adjustment (Chapter 1).
11 Brake pedal height improperly adjusted.
12 Wheel cylinder needs overhaul.
1 3 Improper shoe to drum clearance. Adjust as necessary.
74 Rear brakes lock up under light brake application
1 Tire pressures too high.
2 Tires excessively worn (Chapter 1
75 Rear brakes lock up under heavy brake application
1 Tire pressures too high.
2 Tires excessively worn (Chapter 1
Front brake pads contaminated with oil, mud or water. Clean or
3
replace the pads.
4 Front brake pads excessively worn.
5 Defective master cylinder or caliper assembly.

Suspension and steering

Note: All service procedures for the suspension and steering sys-
tems are included in Chapter 10, unless otherwise noted.
76
Vehicle pulls t o one side
1 Tire pressures uneven (Chapter 1
2 Defective tire (Chapter 1
Excessive wear in suspension or steering components (Chapter 1
3
4
Front end alignment incorrect.
Front brakes dragging. lnspect as described in Section 73.
5
Wheel bearings improperly adjusted (Chapter 1
6
7 Wheel lug nuts loose.
77 Shimmy, shake or vibration
1 Tire or wheel out of balance or out of round. Have them balanced
on the vehicle.
2 Loose, worn or out of adjustment wheel bearings (Chapter 1).
3 Shock absorbers and/or suspension components worn or damaged.
Check for worn bushings in the upper and lower links.
4 Wheel lug nuts loose.
5 lncorrect tire pressures.
6 Excessively worn or damaged tire.
7 Loosely mounted steering gear housing.
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