Three problems related to engine exhaust system have been reported for the 2004 GMC Sierra 2500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 GMC Sierra 2500 based on all problems reported for the 2004 Sierra 2500.
Left and right sides rear exhaust manifold bolts broken off. It leaks exhaust, may be a fire hazard and could cause emissions failure and emissions components failures. This problem is on a 2004 GMC 6. 0 engine. Noticed ticking noise at about 38000 miles and it would go away after 30-45 seconds. A gm rep said it was most likely the skirt less pistons and not to worry. Had some work done at a garage about a week ago and mechanic pointed out the broken bolts.
Bolts that hold exhaust manifold are breaking 3 are gone already I just noticed it today because I heard an exhaust leak unknown how long this has been going on.
Broken exhaust manifold bolts causing excessive noise and emissions issues.