The 2018 GMC Sierra 2500HD represents a rugged and powerful member of GMC's heavy-duty truck lineup. Belonging to its third generation, the Sierra 2500HD came in four trims - Base, SLE, SLT, and the high-end Denali. There were two engine options - a 6.0L V8 delivering 360 horsepower and a turbocharged 6.6L diesel V8 pushing out 445 horsepower. Both engines mated to a six-speed automatic transmission. RWD comes standard, with 4WD as an option. An infotainment system with a 7-inch display, Apple CarPlay, and Android Auto are standard, with navigation and a larger 8-inch display in upper trims. Notable safety features include a rearview camera and an option for forward collision warning. For 2018, a tire fill alert system became standard on all trims.