The muffler heat shield may become loose on the muffler causing a rattle or popping noise. Our technicians tell us there is a kit available from GM to correct this problem.Google+
Car Problem Reports
Chevrolet Silverado 2500 HD Popping Noise From Muffler Heat Shield
Chevrolet Silverado 2500 HD Problem
Exhaust & Emissions Affected: Gasoline
Average Mileage: 109,086 mi (12,000 mi - 204,000 mi)
Visitor, 2001 Chevrolet Silverado 2500 HD, 200,000 mi
The heat shield on top of the muffler has come loose at one corner and now makes an annoying rattle with the engine at an idle. While cruising it usually goes away, however can still be heard at some RPMs.
Visitor, 2001 Chevrolet Silverado 2500 HD, 105,000 mi
Popping noise from muffler heat shield. Mechanic removed the heat shield.
Visitor, 2005 Chevrolet Silverado 2500 HD, 67,500 mi
"vibration" type rattle at around 2200 rpms. The truck has to be under a load meaning in gear. Just revving the engine, in park, will not recreate the noise.
Visitor, 2002 Chevrolet Silverado 2500 HD, 108,000 mi
Muffler seems to hum, sounds like a faint train when truck is started. After it warms up, sound goes away.
Visitor, 2004 Chevrolet Silverado 2500 HD, 105,000 mi
Getting popping crackling noise. Not fixed yet.
Visitor, 2007 Chevrolet Silverado 2500 HD, 65,000 mi
been driving with the rattle. 162,000 now still rattles lol
I have a rattling sound that comes from my heat shield, after the truck is warmed up it goes away. I have yet to have it repaired because it only does it when it's cold and I first start it.
Fabricated new shield with better material.
Visitor, 2008 Chevrolet Silverado 2500 HD, 12,000 mi
Tinny rattling sound when truck in gear under load, doesnt do it idling. Dealers said it was rocks in heat shield but i know this to be not true. Dealer said noise is harmless but it is very annoying.
Visitor, 2001 Chevrolet Silverado 2500 HD, 204,000 mi
Makes a rattling at both an idle and while driving. Doesn't sound good but doesn't affect performance either.