Technical Information - Attachment III
ATTACHMENT III92B11 Program
OWNER NOTIFICATION PROGRAM 92B11
4-WHEEL DISC BRAKE ROUGHNESS
TECHNICAL INSTRUCTIONS
Replace the front brake rotors and linings and check the assembly for hub/rotor stacked runout.
HUB/ROTOR "STACKED" RUNOUT CHECK
If the assembled system (new rotor installed on the hub) indicates more than .002" (.051 mm) total runout (TIR), it will cause excessive thickness variation in the rotor as mileage accumulates by wearing the high spots off the rotor. Excessive thickness variation in the rotor causes brake pulsation and steering wheel shake.
High system runout (TIR) is caused by...
^ Rust/contamination trapped between the hub and rotor mounting surface
^ Rotor or hub (high and low spots) not properly positioned during assembly.
ROTOR REPLACEMENT
1. Clean the hub area that will contact the new rotor. Remove all rust build-up and debris.
2. Install a new rotor (FOSZ-1L104-A for 1989/1990 vehicles and FISZ-1125-A for 1991 vehicles) on the hub. Tighten the lug nuts to 10 lb.ft. (13 N-m) for testing.
3. Using a dial indicator (TOOL-4201-C) or equivalent, determine the total runout of the system. See Figure 1. The total system (rotor and hub) runout must not exceed .002" (.051 mm).
4. If the runout exceeded .002" (.051 mm), rust/contamination could still be trapped between the hub and rotor mounting surface or the rotor and hub (high and low spots) are not properly positioned together. Proceed as follows:
a. Remove the rotor and reclean the hub and rotor mounting surfaces. Rotate the rotor on the hub clockwise until the next hole lines up with the stud.
b. Secure the rotor in the new position, as described in Step 2 and recheck the runout as described in Step 3.
c. Repeat the checking and rotation (reindexing process) until the system measures .002" (.051 mm) or less total runout.
FRONT BRAKE SHOE AND LINING ASSEMBLY REPLACEMENT
1. Install a new set of non-abrasive front brake shoe and lining assemblies. Only Use front brake shoe and lining kit F1SZ-2001-A.
2. Refer to the appropriate Thunderbird/Cougar Service Manual for service details.
MUTILATE AND SCRAP THE REMOVED PARTS.