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Brake System Trouble Shooting

NOTE: This is GENERAL  information. This article is not intended to be specific to any unique situation or individual vehicle configuration. The purpose of this Trouble Shooting information is to provide a list of common causes to problem symptoms. For model-specific Trouble Shooting, refer to SUBJECT, DIAGNOSTIC, or TESTING articles available in the section(s) you are accessing.
BRAKE SYSTEM TROUBLE SHOOTING CHART

CONDITION & POSSIBLE CAUSE CORRECTION
Brakes Pull Left or Right
Incorrect tire pressure Inflate tires to proper pressure
Front end out of alignment See WHEEL ALIGNMENT
Mismatched tires Check tires sizes
Restricted brake lines or hoses Check hose routing
Loose or malfunctioning caliper See DISC BRAKES or BRAKE SYSTEM
Bent shoe or oily linings See DRUM BRAKES or BRAKE SYSTEM
Malfunctioning rear brakes See DRUM, DISC BRAKES or BRAKE SYSTEM
Loose suspension parts See SUSPENSION
Noises Without Brakes Applied
Front linings worn out Replace linings
Dust or oil on drums or rotors See DRUM, DISC BRAKES or BRAKE SYSTEM
Noises With Brakes Applied
Insulator on outboard shoe damaged See DISC BRAKES or BRAKE SYSTEM
Incorrect pads or linings Replace pads or linings
Brake Rough, Chatters or Pulsates
Excessive lateral runout Check rotor runout
Parallelism not to specifications Reface or replace rotor
Wheel bearings not adjusted See SUSPENSION
Rear drums out-of-round Reface or replace drums
Disc pad reversed, steel against rotor Remove and reinstall pad
Excessive Pedal Effort
Malfunctioning power unit See POWER BRAKES or BRAKE SYSTEM
Partial system failure Check fluid and pipes
Worn disc pad or lining Replace pad or lining
Caliper piston stuck or sluggish See DISC BRAKES or BRAKE SYSTEM
Master cylinder piston stuck See MASTER CYLINDERS or BRAKE SYSTEM
Brake fade due to incorrect pads for linings Replace pads or linings
Linings or pads glazed Replace pads or linings
Worn drums Reface or replace drums
Excessive Pedal Travel
Partial brake system failure Check fluid and pipes
Insufficient fluid in master cylinder See MASTER CYLINDERS or BRAKE SYSTEM
Air trapped in system See BRAKE BLEEDING or BRAKE SYSTEM
Rear brakes not adjusted See Adjustments in DRUM BRAKES or BRAKE SYSTEM
Bent shoe or lining See DRUM BRAKES or BRAKE SYSTEM
Plugged master cylinder cap See MASTER CYLINDERS or BRAKE SYSTEM
Improper brake fluid Replace brake fluid
Pedal Travel Decreasing
Compensating port plugged See MASTER CYLINDERS or BRAKE SYSTEM
Swollen cup in master cylinder See MASTER CYLINDERS or BRAKE SYSTEM
Master cylinder piston not returning See MASTER CYLINDERS or BRAKE SYSTEM
Weak shoe retracting springs See DRUM BRAKES BRAKE SYSTEM
Wheel cylinder piston sticking See DRUM BRAKES or BRAKE SYSTEM
Dragging Brakes
Master cylinder pistons not returning See MASTER CYLINDERS BRAKE SYSTEM
Restricted brake lines or hoses Check line routing
Incorrect parking brake adjustment See DRUM BRAKES BRAKE SYSTEM
Parking Brake cables frozen See DRUM BRAKES BRAKE SYSTEM
Incorrect installation of inboard disc pad Remove and replace correctly
Power booster output rod too long See POWER BRAKE UNITS BRAKE SYSTEM
Brake pedal not returning freely See DISC, DRUM BRAKES BRAKE SYSTEM
Brakes Grab or Uneven Braking Action
Malfunction of combination valve See CONTROL VALVE or BRAKE SYSTEM
Malfunction of power brake unit See POWER BRAKE UNITS or BRAKE SYSTEM
Binding brake pedal See DISC, DRUM BRAKES or BRAKE SYSTEM
Pulsation or Roughness
Uneven pad wear caused by caliper See DISC BRAKES or BRAKE SYSTEM
Uneven rotor wear See DISC BRAKES or BRAKE SYSTEM
Drums out-of-round Reface or replace drums