GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 TopKick C-Series (Conventional) C6/C7/C8 🢒 Preface 🢒 Dangers, Warnings, and Cautions 🢒 Exhaust Leakage

Problem

Action

Warning: Refer to Hot Exhaust System Warning in the Preface section.

DEFINITION: An exhaust leak may show stains at the area of the leak. The leak may be felt by holding a hand close to the suspected areas or using a smoke pencil. The leak may make a popping or hissing noise.

Refer to Symptoms - Engine Exhaust prior to beginning this table.

Misaligned or improperly installed exhaust system components
    • Align and tighten the exhaust system components to the specifications. Refer to Fastener Tightening Specifications.
    • Ensure the exhaust hangers are in the proper locations and not loose. Refer to Exhaust System Insulator, Hanger, Bracket Replacement.

Exhaust leaks at the following connections:

    • Exhaust manifold to pipe
    • Flanges
    • Pipe clamps

Tighten the components to the specifications. Refer to Fastener Tightening Specifications.

Seals or gaskets leaking

    • Exhaust manifold to cylinder head
    • Exhaust pipes to exhaust manifold
    • Catalytic converter connection
    • EGR connections
    • AIR connections to the exhaust manifold or cylinder head

Replace the leaking seal or gasket. Refer to the affected components procedure for service.

Irregularities at the mating surfaces on the flange connections

Repair as required or replace the affected component. Refer to the affected components procedure for service.

Exhaust manifold cracked or broken

Replace the exhaust manifold. Refer to the following procedures:

Exhaust system component connection welds leaking

Replace the leaking component. Refer to the affected component procedure for service.

Muffler damaged or leaking at the seams

Replace the affected muffler or resonator. Refer to Exhaust Muffler Replacement.