Brakes (Front) - Caliper Mounting Bolt Bore Corrosion

Bulletin Number:
92-5-6A

Reference Number:
135017R

Publish Date:
10/92



Subject:
FRONT DISC BRAKE CALIPER BOLT BORE CORROSION (REPLACE BOLT AND SLEEVE ASSEMBLY/BUSHINGS)

Models Affected:
1990-92 SUNBIRD AND GRAND AM AND
1990-91 BONNEVILLE MODELS

THIS BULLETIN IS BEING REVISED TO CORRECT THE MODELS AFFECTED. THIS BULLETIN CANCELS AND REPLACES BULLETIN 92-5-6 ISSUED 11/91. PLEASE DISCARD BULLETIN 92-5-6.

CONDITION:

Some 1990-92 Sunbird and Grand Am and 1990-91 Bonneville models may experience a condition of a caliper not sliding freely or moving on the mounting bolts inward toward the center of the vehicle.

CAUSE:





This condition is due to corrosion in the caliper mounting bolt area (See Figure 1) caused by contaminates seeping past the mounting bolt rubber bushing.



CORRECTION:

Inspect the caliper suspension mounting bolts and sleeves for corrosion. Also, inspect the bushings for cuts, nicks and/or excessive wear. If damage to either part is found, replace with new parts.

IMPORTANT:
Do Not attempt to polish away corrosion from the bolt or sleeve assemblies.

Lubricate the bushing bore with silicone grease, contained in Bushing Kit, P/N 18017226 or equivalent and install bolt and sleeve assembly. The bolt and sleeve assembly should slide through the bushing without the use of mechanical assistance. If the force required to slide the bolt and sleeve exceeds hand assembly pressure, remove the bushings and inspect the mounting bores for corrosion.


* If bores show signs of corrosion, clean the bores with a one inch wheel cylinder honing brush.

IMPORTANT:
Replace rubber bushings with new parts contained in service kit, P/N 18017226 whenever they are removed from housing.

Parts are currently available from GMSPO.

Labor Operation Number:
T1781

Labor Time:
1.2 Hours

Trouble Code:
92