For Lowell, MI drivers needing raw power and capability, the 2025 GMC Sierra 3500 HD Chassis Cab delivers impressive performance. This heavy-duty workhorse comes with your choice of a standard 6.6-liter V8 gasoline engine generating 401 horsepower and 464 pound-feet of torque, or an available 6.6-liter turbodiesel V8 cranking out 470 horsepower and a massive 975 pound-feet of torque. Both pair with a smooth-shifting Allison 10-speed automatic transmission.