Table 1 shows nine common engine and engine cooling related problems of the 2005 GMC Sierra 1500. The number one most common problem is related to the engine and engine cooling (five problems). The second most common problem is related to the manifold/header/muffler/tail pipe (four problems).
Castech cylinder heads on 2001 through 2006 5. 3l vortec engines are porous and allow antifreeze to seap into the oil. This is a safety concern as it can destroy the engine (oil doesn't lubricate correctly, sludge buildup) and leave someone, at the least, stranded, at the worst, it can cause a huge Read details...
Exhaust manifold bolts on each side of engin snapped off for no appearant reason / normal use, big concern of exaust fumes entering the cab Read details...
GMC pickup developed coolant loss. Took in and found that head had cracked. Service bulletin revealed 50% of heads for that year came from one manufacturer and had been prone to cracking. Discovered mine indeed had the suspect head and did have the crack as described. Read details...