After recently presenting its revised 2027 Chevrolet Silverado 1500 and GMC Sierra 1500, General Motors rolls out the bigger guns, with the updated 2027 heavy-duty pickup lineup. The 2027 Chevrolet Silverado HD and GMC Sierra HD get substantial mechanical revisions; namely, the new trucks feature an all-new in-house diesel engine alongside segment-first steering and braking architectures.
Powertrains of the 2027 Chevrolet Silverado HD and GMC Sierra HD
Central to the 2027 update is the available 8.3L Duramax Turbo-Diesel V8 (DK68). This marks GM’s first heavy-duty diesel engine fully designed, developed and manufactured in-house. Built on a compacted graphite iron block with a forged crankshaft and steel pistons, the engine produces 555 hp and 1,230 lb-ft of torque. It incorporates a dual-stage air-to-water charge cooling system and a variable-geometry turbocharger, paired with an Allison 10-speed transmission.
The standard 6.6L gas V8 also receives revisions, including a new Turbo-Jet intake manifold and upgraded lubrication system, pushing output to 412 hp and 472 lb-ft of torque. Properly equipped models can hit a maximum gooseneck towing capacity of up to 38,000 lb (17,236 kg) and a gross combined weight rating (GCWR) of 46,500 lb (21,092 kg).
Chassis, steering and braking firsts
The 2027 HD lineup replaces traditional hydraulic steering with a segment-first rack-and-pinion Electric Power Steering (EPS) system. GM says the setup provides around 30 percent more power assist than the previous hydraulic gear, reducing steering kickback and noise while improving low-speed manoeuvrability.
Accompanying the EPS is a new electronic brake-boost system paired with larger brakes and four-piston front calipers. According to GM, the eBoost architecture cuts stopping distances by up to 20 percent when hauling a trailer.
GM also expanded the trucks’ drive-mode calibrations; the ZR2 and AT4X off-road variants feature a new Terrain Mode, which allows for one-pedal driving in both 4HI and 4LO settings.
Canadian engineering and manufacturing
GM vaunts the Canadian connection to its 2027 heavy-duty lineup. For one, the Canadian Technical Centre led the development of several integrated control and trailering technologies. For another, GM’s Oshawa Assembly plant in Ontario will continue building the Chevrolet Silverado HD and has been confirmed to assemble both next-generation heavy-duty models.
Engine assembly for the 8.3L Duramax will take place at the expanded DMAX facility in Brookville, Ohio, which is benefiting from a $920 million USD investment.
The updated 2027 Chevrolet Silverado HD and GMC Sierra HD are expected to reach Canadian dealerships in late 2026, with pricing details to be released closer to launch.
