Exhaust System - Moan

90buick06
Bulletin: 88-6F-5

Date: Apr. '90

Ref. No.: 88-297-6F

Corp. Ref. No.: 076601R

SUBJECT: EXHAUST MOAN - INSTALL DAMPENER ON EXHAUST PIPE REAR OF THE CATALYTIC CONVERTER

MODELS AFFECTED: 1982 - 1988 SKYHAWK (VIN CODES K, G, P AND 0)

Some customers may comment about an exhaust moan or boom that occurs primarily at 1900 rpm and at 2400 rpm.



This condition can be corrected by installing a mass dampener, (P/N 10137382) using a 2-inch exhaust clamp (P/N 1261589) per the following instructions and illustration.

1. Remove the nuts and saddle from the clamp assembly. Discard one of the nuts.

2. The clamp assembly may be located directly behind the catalytic converter flange, as long as there is sufficient clearance to heat shields.

Do not install the dampener/clamp assembly rearward of the downward bend in the exhaust pipe; there will not be enough ground clearance at this location.

3. Position the saddle on the clamp and install the dampener hand-tight onto one side of the clamp (whichever side has the most clearance from the underbody heat shields).

4. Install one nut on the other side of the clamp and torque it to 20 N-m (14.8 lbs.ft.). Check the torque of the dampener to make sure that it is at least 20 N-m (14.8 lbs.ft.), using a torque wrench with an open end head (crowfoot). Do not over-torque the dampener or the clamp nut, or the exhaust pipe may be crushed.

5. Do NOT install a nut on the dampener side of the clamp assembly.

Parts are available from GMSPO.

WARRANTY INFORMATION:

Labor Operation Number: T4655
Labor Time: 0.2 hrs.
Trouble Code: 92