Table 1 shows nine common engine and engine cooling related problems of the 2020 GMC Sierra 1500. The number one most common problem is related to the engine and engine cooling (192 problems). The second most common problem is related to the gas recirculation valve (egr valve) (four problems).
2020 GMC Sierra 1500 began experiencing a slight knocking sound - mechanic diagnosed as a crankshaft issue. As of last night, 5/10, the truck's knocking sound got extremely loud, the exhaust pipe emitted smoke, and the truck began "bucking. " no warning messages or lamps appeared. Read details...
1. On 05/9/25, the exhaust emissions system malfunctioned, triggering diagnostic trouble code p2c7a (exhaust emissions system failure). This repair, the seventh attempt since June 2024, addressed the same recurring emissions issue previously involving replacements of components such as the nox Read details...
Tick sound coming from underneath. Also fumes smell. Dealership found it to be the exhaust system. Said the muffler valve is bad. Quoted me $2000 for repair. Never heard of a exhaust system failure in only 5 years. Very unsatisfied with this. Read details...