Four problems related to manifold/header/muffler/tail pipe have been reported for the 2003 Chevrolet Silverado 1500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Chevrolet Silverado 1500 based on all problems reported for the 2003 Silverado 1500.
Several of the exhaust manifold bolts have snapped/sheared causing exhaust leaks between the exhaust manifold and exhaust port on the cylinder head. I'm learning that this is a common issue that has gone unaddressed by the manufacturer, but is clearly an emissions and functionality issue. Please help in holding the manufacturer accountable for this apparent mechanical defect. As of now, they offer no assistance in repairing the issue.
The contact owns 2003 Chevrolet Silverado 1500 hd. The contact stated that the vehicle was making a loud noise. After inspecting the vehicle he noticed that four of the exhaust header manifold bolt heads were missing. The vehicle was taken to a dealer. The technician diagnose that the exhaust manifolds and bolts needed to be replaced. The vehicle was not repaired. The manufacturer has been notified of the failure. The approximate failure mileage was 108,000.
Exhaust manifold bolts breaking off leaving studs in the heads (4) my late 2002 chevy z71 developed an exhaust leak and the catalytic converter started banging at idle or after parked. Engine has black exhaust on the head where we found the main leak. So, carbon monoxide has been coming into the cab and the engine compartment seems hotter than normal. When checking into the issue, I found every truck in our company fleet has this same issue and our associates that have personal trucks driving to work checked theirs and they also have the same issue. From 1999 thru 2008 years. When contacting our local chevy dealer, they advised they had never seen or heard of any issues like this. I find that hard to believe. Every person I mention this to, checks their truck and has the same issues with the broken bolts. There is definitely a problem with the exhaust manifold contracting and expanding too much- cheap steel attached to aluminum heads appear on all of the v-8 truck engines. Please look into this as a safety issue with heat and carbon monoxide as well as the costs to repair.
August 2007 purchased 2003 Chevrolet silverado 41,000 miles found out after purchase manifold bolts on drivers side and passenger side were broke. Took vehicle into Chevrolet dealer had left side manifold replaced and bought up grade bolts from gm. As of February 2, 2011 manifold bolts are breaking again causing manifold leak which is a violation of emissions and also can cause a fire hazard if this problem isn't addressed that gm has faulty manifolds someone may end up seriously injured. The truck now has 72,000 miles on it dealership was notified of the second problem and no help was given.