Exhaust - Muffler Tone Louder Than Normal

BULLETIN NUMBER:
92-6F-150

SECTION:
6F

NUMBER:
1

CORPORATE
REFERENCE NUMBER:
266603

DATE:
December 1992



SUBJECT:
L35 MUFFLER TONE QUALITY (DIAGNOSE/INSTALL RETUNED MUFFLER)

MODELS:
1992 S/T UTILITIES WITH 4.3L (L35) ENGINES



Owners of some 1992 S/T Utility vehicles with 4.3L CPI engines (L35) built before the VIN breakpoints listed below may comment on louder than normal exhaust noise. A retuned muffler is currently available which will reduce the amount of audible noise.

VEHICLES INVOLVED
Pontiac West Assembly Plant:

Make Built Before VIN
GMC 1GTCS14R9NO515773

Moraine Assembly Plant:

Make Built Before VIN
GMC 1GKDT13W8N2531932

SERVICE PROCEDURE

Removing Exhaust Parts:

CAUTION:
Always wear protective goggles and gloves when removing exhaust parts as failing rust and sharp edges from worn exhaust components could result in serious personal injury. Using a penetrating oil on the threads of u-bolts can assist In the removal of the exhaust components.



Installing Exhaust Parts:

When installing a new muffler and tailpipe, on any model, check for proper alignment. Rattles and noise vibrations in the exhaust system are usually caused by a misalignment of parts. When aligning the system, leave all bolts or nuts loose until all parts are properly aligned, then tighten, working from the front to rear. Exhaust system hangers, hanger brackets, and clamps which are damaged should be replaced to maintain exhaust system alignment. Refer to X-9229 Sonoma and Jimmy Service Manual section 6F Exhaust System for additional information.

SERVICE PARTS INFORMATION

Part Number Description
12541384 Muffler - 2 Dr. and 4 Dr. Jimmy
15662532 Tailpipe - 2 Dr. Jimmy
15662531 Tailpipe - 4 Dr. Jimmy
15595048 Clamp - 2 Dr. and 4 Dr. Jimmy

Parts are currently available from GMSPO.

WARRANTY INFORMATION
For vehicles repaired under warranty use:

Labor Operation: L2584

Labor Time: 0.4 hrs.