1996 Bronco/F-Series

Section 06-05: Brake System, Parking

1996 Bronco, F-150, F-250, F-350, F-Super Duty Chassis Cab and Motorhome Chassis Vehicles Workshop Manual

DIAGNOSIS AND TESTING

Symptom Chart — Parking Brake System

SYMPTOM CHART — PARKING BRAKE SYSTEM
Condition	Possible Source	Action
Squeals or Groans	Glazed linings.	REMOVE glaze from linings using a file or emery cloth.
	Misaligning of parts.	CORRECT misalignment by TIGHTENING any loose brake or drum mounting bolts.
	Dirt in brake drum.	REMOVE brake drum and CLEAN out lining dust and dirt.
Scraping Noise	Worn out parking brake shoe and lining.	CHECK for lining worn down to rivets — REPLACE shoes if necessary.
	Bent or misaligned parking brake shoe and lining.	CHECK for misaligned shoe, rubbing against brake drum. REPLACE parking brake shoes if necessary.
Clicks	Excessive clearance.	ADJUST cable clevis.
	Eccentric or wobbling brake drum.	INSPECT drum runout. Also CHECK for worn or loose input or output bearings on mainshaft. CHECK drum mounting bolts for tightness.
	Excessive linkage friction.	CHECK linkage pivot points for rust, binding, or lack of lubrication.
Grabbing	Transmission fluid on parking brake shoe and lining.	REPLACE parking brake linings. CLEAN oil and excess brake lubricant from brake and brake drum. REPLACE faulty oil seal at mainshaft.
Parking Brake Will Not Apply	Excessive clearance prevents complete brake application.	ADJUST brake lining cable to take up slack in brake linkage.
	Grease-soaked linings.	REPAIR source of leak, INSTALL new linings.
	Excessive linkage friction.	CHECK for linkage binding, and misalignment. LUBRICATE all pivot points.
	Worn out linings.	REPLACE parking brake shoe and lining. CHECK drum/yoke for scoring and REPLACE if necessary. GO to Pinpoint Test A.
Parking Brake Will Not Release	Brake drag.	ADJUST parking brake cables or service binding condition. INSPECT for broken or missing springs.
	Rough brake drum surface.	SMOOTH brake drum with emery paper, or REPLACE if brake drum is badly scored. CAUTION: Brake drum to be replaced if inside diameter exceeds 229.36mm (9.030 inches). GO to Pinpoint Test B.

PINPOINT TEST A: PARKING BRAKE WILL NOT APPLY

A1 CHECK PARKING BRAKE CONTROL

Operate the parking brake control.

Does parking brake control operate smoothly?

Yes	No
GO to A2.	SERVICE binding condition in parking brake control and RETEST system.

A2 CHECK PARKING BRAKE CABLES

Raise and support vehicle.
Inspect for broken or binding parking brake cables.

Is there a parking brake cable concern?

Yes	No
SERVICE parking brake cables as required. RETEST system.	GO to A3.

A3 CHECK PARKING BRAKE COMPONENTS

Raise and support the vehicle.
On all except F-Super Duty, removebrake drums.
Operate the parking brake control and observe the parking brake components.

Do the parking brake components operate?

Yes	No
ADJUST the parking brake as described in this section. RETEST system.	SERVICE worn or damaged parts. RETEST the system. For F-Super Duty, REMOVE the parking brake assembly and SERVICE as necessary.

PINPOINT TEST B: PARKING BRAKE WILL NOT RELEASE

B1 CHECK PARKING BRAKE CABLE

Release parking brake control.
On F-Super Duty, if the vehicle can't be moved, raise and support the vehicle.
Release parking brake cable tension.
On all but F-Super Duty, remove brake drum and disconnect parking brake rear cable and conduit.

Does the parking brake release?

Yes	No
GO to B2.	For F-Super Duty, REMOVE the parking brake assembly and SERVICE as necessary. For all other vehicles, SERVICE the worn or damaged rear brake component. RETEST the system.

B2 PARKING BRAKE CABLE CHECK

Release the parking brake control.

Does the parking brake control release?

Yes	No
INSPECT parking brake cable for binding. SERVICE as necessary. RETEST system.	SERVICE the worn or damaged parking brake control. RETEST the system.