Subject: | Jingling Noise On Deceleration or Coast Down (Section and Replace Intermediate Exhaust) |
Models: | 2002-2004 Chevrolet Corvette |
This bulletin is being revised to clarify the correct part numbers for the gasket and clamp. Please discard Corporate Bulletin Number 04-06-05-006 (Section 06 - Engine).
Some customers may comment on an undesirable "jingle" or "jingling" type of noise when decelerating. The noise is similar to shaking a key ring. This condition is most prominent at the mid- to high-rpm range. This noise may also be noticed when driving next to a cement wall or other barrier that will deflect sound.
This noise is coming from the "H" pipe area of the exhaust system. The center part of the "H" is formed by a crossover pipe connecting the left and right exhaust pipes. At this point, turbulence builds up in the exhaust system and may produce a jingle noise.
A service section of the exhaust has been released that incorporates a revised crossover pipe. You will need to cut the original exhaust behind the catalytic converters as described in the procedure below.
Caution: This procedure requires metal cutting. You MUST wear protective goggles and gloves.
• | Measurements need to be made from the forward edge of the crossbrace welded to the pipes. |
• | The most accurate measurement can be achieved by running a measuring tape between the catalytic converters rather than over them down the length of the pipe. In order to measure over the converters, you will have to arc the tape which will result in an inaccurate measurement. |
Notice: You must make sure that no burrs remain at the cut point. In addition, the area up to 18 cm (7 in) back from the cut should be clean, smooth and free of metal fragments or burrs. Failure to properly prepare the surface may result in an exhaust leak.
Tighten
Tighten the flange bolts to 20 N·m(15 lb ft).
Tighten
Tighten the exhaust clamps to 44 N·m(32 lb ft).
Part Number | Description | Qty |
---|---|---|
10276792 | Gasket, Exhaust -- Rear Flange | 2 |
10345549 | Clamp, 2 1/2" Exhaust | 2 |
10352196 | Pipe, Intermediate (Service Section) | 1 |
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
---|---|---|
L3504* | Pipe, Intermediate Section -- Install | 0.6 hr |
*This labor operation is for bulletin use only. It will not be published in the Labor Time Guide. |