2027 GMC Sierra 2500 HD, 3500 HD Revealed: 7 Trims, New Gas or Diesel V8s

Like its companion heavy-duty Silverados, the 2027 GMC Sierra HDs will get GM’s most powerful engines ever for the lineup, along with new steering, braking and trailer technology.

Also like the Silverado HDs, the pickups aren’t slated for a redesign for 2027. The next-gen models are expected for 2029. The Silverado 1500 and Sierra 1500, however, are getting redesigned for 2027.

Though the signature GMC grilles, LED projector headlamps and squared-off lines will remain, the big change for the Sierra 2500 HD and 3500 HD will be under the hood with new engines GM is calling its “most powerful yet.”

The 2027 Sierra HD will also come in seven trims: Pro, SLE, SLT, AT4, AT4X, Denali and Denali Ultimate.

The new pickups are set to be available by the end of the year, along with pricing.

The Engines

Buyers of the 2500 HD and 3500 HD will get a choice of GM’s newest diesel and gas V8s.

The standard “Enhanced 6.6L gas V8” boasts the following specs:

• 412 horsepower
• 472 lb.-ft. of torque
• 19,000 lbs. max available towing (2500 HD)

Specs for the available Duramax 8.3L Turbo-Diesel V8:

• 555 horsepower (best-in-class)
• 1,230 lb.-ft. of torque (best-in-class)
• 38,000 lbs. max available towing (3500 HD)

The Tech

"Intelligent trailering tech"GMCThe 2027 heavy-duty pickups will be the first Sierra HDs to get these new features:

• Electric power steering — electrically assisted rack-and-pinion steering system designed for nimble maneuvering on switchbacks, fitting into tight spaces and reduced maintenance. It also delivers quieter operation with no hydraulic noise and reduces steering kickback when off-road, the company says.
• eBoost braking — uses advanced technology to deliver added stopping power under load, especially on long downhill grades or when making repeated stops while towing, according to GM.

For hauling, the Sierra HDs get these available additions:

• Up to 14 available camera views, including Transparent Trailer View, Bed View and Surround Vision.
• In-vehicle trailering app.
• Trailer Side Blind Zone Alert.
• Trailer tire pressure and temperature monitoring.
• Hitch guidance system.
• Trailer sway control.
• Adaptive Cruise Control with trailering capability.

The Trims

The seven trims for the Sierra HD include base, off-road and luxury versions:

Pro

• 6.6L V8 gas engine with Allison 10-speed automatic transmission.
• Adaptive Cruise Control with trailering capability.
• Trailering Package, Trailering Mirrors and Trailer Brake Controller.

SLE

• 13.4-inch-diagonal Premium GMC Infotainment System.
• 12.3-inch-diagonal digital Driver Information Center.
• Traction Select System with Tow/Haul mode.
• 18-inch machined aluminum wheels. 

SLT

• Available 10-way power-adjustable, heated and ventilated front bucket seats with perforated leather appointments.
• Heated steering wheel.
• ProGrade Trailering System with In-Vehicle Trailering App.

2027 GMC Sierra HD AT4GMCAT4

• Exclusive Jet Black interior with Kalahari accents.
• Heated and ventilated perforated front leather seating surfaces.
• Exclusive 20-inch Gloss Black aluminum wheels with available BFGoodrich All-Terrain tires.
• Off-Road Suspension Package with twin-tube shocks and skid plates.

AT4XAT4X

• Factory-installed 1.5-inch suspension lift, Multimatic DSSV dampers, rear electronic-locking differential, larger steel transfer case skid plate and front aluminum skid plate.
• 35-inch Goodyear Territory MT tires.
• 16-way heated and ventilated power front seats with massage feature.

DenaliDenali

• 20-inch Ultra-Bright machined aluminum wheels with bright chrome inserts.
• Denali-exclusive authentic wood, patterned aluminum trim and Forge perforated leather seating surfaces.
• 12-way heated and ventilated power front seats.

Denali UltimateDenali Ultimate

• Duramax 8.3L Turbo-Diesel V8 engine with Allison 10-speed automatic transmission.
• Signature Vader Chrome grille.
• Exclusive 20-inch Ultra-Bright machined aluminum wheels with Gloss Black inserts.
• Exclusive Alpine Umber interior featuring full-grain leather seating, authentic Paldao wood and 16-way power front seats with massage feature. 

More Photos

AT4

AT4X

Denali