Bravada 2WD L6-4.2L VIN S (2002)
Exhaust Manifold Gasket: Customer Interest
Exhaust - Exhaust Noise/Leak
File in Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-01-032
Date: October, 2002
TECHNICAL
Subject:
Exhaust Noise/Leak
(Replace Exhaust Manifold Fasteners and Gasket)
Models:
2002 Chevrolet TrailBlazer
2002 GMC Envoy
2002 Oldsmobile Bravada
with 4.2L Engine (VIN S - RPO LL8) and Automatic Transmission (RPO M30) Built from Start of Production to January, 2002
Condition
Some customers may comment on an exhaust noise or exhaust leak. The noise will appear to come from the area of the exhaust manifold.
Cause
The fasteners used to hold the exhaust manifold may have relaxed and lost clamping power. The manifold will then be allowed to move under certain
conditions causing a small leak.
Correction
Install a new exhaust manifold gasket and fasteners. Use the part numbers listed below.
The new fasteners have the proper adhesive in patch form already on the threads. DO NOT use any additional thread lock material.
1.
Remove the exhaust manifold fasteners and gasket and dispose of properly.
2.
Make sure the manifold bolt holes in the cylinder head are clean of debris or foreign material.
3.
Install a new exhaust manifold gasket.
4.
Install the exhaust manifold using new fasteners.
5.
Tighten all fasteners in sequence to 20 N.m (15 lb ft).
6.
Tighten each fastener a second time with the same sequence and torque.
