New 2027 GMC Sierra 1500 Has 2 New V8 Engines

The 2027 GMC Sierra 1500 is shaping up to be much more than a routine update. GMC has reworked the truck inside and out, but some of the biggest news is happening underneath the hood. The next generation Sierra introduces 2 new V8 engines, keeps the popular 3.0-liter diesel, adds more towing technology, and completely transforms the cabin with more than 60 inches of combined digital displays.

For buyers who still want a traditional gasoline V8 in their full-size pickup, GMC is giving them 2 very different choices. The first is an all-new 5.7-liter V8 producing 402 horsepower and 428 pound-feet of torque. Although the 5.7-liter displacement has plenty of history within General Motors, this is a new engine developed for the latest Sierra.

GMC sees the 5.7-liter as the workhorse of the new engine family. It will be offered across a broad portion of the Sierra lineup, ranging from work-oriented trucks all the way up to the luxurious Denali. More importantly, this is the engine buyers will want to look at if maximum towing capacity is the priority.

When properly configured with the Max Trailering package, the 5.7-liter Sierra 1500 can tow as much as 13,500 pounds. That is a serious figure for a half-ton pickup and helps explain why GMC has positioned this engine differently from the larger 6.6-liter V8.

That 6.6-liter engine is where things get especially interesting for buyers more concerned about performance. It produces 481 horsepower and 501 pound-feet of torque, making it the most powerful of the gasoline engines discussed for the new Sierra.

Instead of simply using the largest engine to achieve the biggest towing number, GMC has taken a different approach. The 6.6-liter V8 is aimed more toward drivers looking for horsepower, torque, acceleration, and a more performance-oriented personality. It still offers substantial capability, with a towing capacity of up to 9,400 pounds, but its main attraction is the extra power.

The 6.6-liter will be offered in premium configurations including the Denali and AT4X. In the Denali, GMC pairs the engine with a dedicated Sport mode. Selecting that mode changes more than a graphic on a display. The truck integrates the powertrain with other systems, including the active exhaust, steering, and adaptive suspension, to create a more performance-focused driving experience.

The AT4X takes the same basic idea in another direction. Here, the 6.6-liter V8 can work with a new Baja mode designed for higher-speed off-road driving. The AT4X also features Multimatic shock absorbers, giving GMC an opportunity to coordinate the engine, transmission, suspension, and other vehicle systems when the truck is being driven aggressively away from pavement.

Both V8 engines use 10-speed automatic transmissions, while axle ratios have been optimized around their intended applications.

The 3.0-liter diesel remains an important part of the Sierra lineup as well. Unlike the 2 new gasoline V8 engines, the diesel is essentially a carryover powertrain. It continues to produce 305 horsepower and 495 pound-feet of torque.

Those numbers may not grab attention like 481 horsepower from the 6.6-liter V8, but the diesel has a very different mission. Its combination of torque, towing ability, efficiency, and driving range continues to make it one of the most interesting engines available in the Sierra 1500.

GMC says the 3.0-liter diesel will be available throughout the Sierra range, starting with the Work Truck and extending all the way to the AT4X. When properly configured with the Max Trailering package, GMC says the diesel will have a trailer rating of more than 12,000 pounds.

There is another major advantage for drivers who spend a lot of time on the highway. GMC is introducing an optional 34-gallon fuel tank for the diesel. Combined with the efficiency of the 3.0-liter engine, GMC says this configuration can deliver more than 900 miles of driving range from a tank of fuel.

The 6.6-liter V8 also receives a 34-gallon tank as standard equipment.

While the powertrain lineup is likely to attract plenty of attention, GMC has made equally dramatic changes inside the Sierra.

The dashboard has been completely redesigned with a flatter layout intended to make the cabin feel wider and more open. Technology dominates the new interior, with GMC claiming more than 60 inches of combined digital display area.

That collection includes a 12.2-inch driver information display, a 15-inch head-up display, an 8.5-inch rear camera mirror, a 16.3-inch center display, and an 11.5-inch front passenger screen.

The 16.3-inch center display has one of the more unusual features in the truck. On appropriately equipped models, the entire display can electronically rise at the press of a button, revealing a hidden storage compartment behind it. The articulating function will be included on Elevation models and above.

The passenger gets a dedicated 11.5-inch display that can open and close and is designed so its content is not easily visible from the driver’s seating position. That allows the passenger to access entertainment without creating the same level of distraction for the driver. Available entertainment functionality discussed for the system includes services such as Netflix, Disney Plus, AMC television, and YouTube television.

GMC has not abandoned physical controls either. Important functions remain accessible through dedicated buttons rather than forcing the driver to navigate through touchscreen menus for everything. That combination could be important for truck buyers who want modern technology without losing quick access to frequently used vehicle controls.

The center console has also been redesigned. GMC calls it the MultiPro center console, and it can be configured in different ways depending on what the driver needs. It offers additional storage, 2 wireless charging locations, and a section that can flip forward to create a work surface.

Connectivity is another major focus. The cabin incorporates multiple Universal Serial Bus Type C ports along with a High Definition Multimedia Interface connection that can work with the passenger display. There are also 120-volt power outlets available in the cabin and bed.

For the first time, the Sierra will also offer a panoramic sunroof with opening and tilting functionality along with a sunshade.

Interior materials vary depending on the trim. The AT4X shown during the presentation featured a Timber Mahogany interior along with carbon fiber accents. The Denali Ultimate takes a more luxury-oriented approach with open-pore birch wood trim. A 16-speaker Bose premium audio system is also available, with stainless steel speaker elements integrated into areas including the doors and head restraints.

GMC has made some smaller changes in the rear cabin as well. The previous 3-panel rear window has been replaced by a simpler single rear window design, while the rear seatback pockets have been removed to give the area a cleaner and more open appearance. Under-seat storage continues to be available.

Outside, the AT4X demonstrates how GMC is evolving the Sierra without completely changing its identity. The truck receives a redesigned front end and new light-emitting diode lighting while retaining the upright, substantial appearance expected from a Sierra.

The AT4X shown at the event was equipped with large Goodyear Wrangler Territory mud-terrain tires measuring 285/75R18. GMC avoids deployable running boards on this version in order to preserve the ground clearance expected from the more off-road-focused model.

The familiar MultiPro tailgate remains, along with useful truck features such as bed lighting and GMC’s integrated corner steps.

Technology is also expanding beyond infotainment. Super Cruise will now be offered on the AT4 and AT4X, bringing GMC’s hands-free driving technology into Sierra configurations designed with off-road capability in mind.

Trailering technology is receiving attention too. A new trailer brake gain auto assist system is designed to simplify the process of setting the proper trailer brake gain, particularly for drivers who may not have extensive towing experience.

The truck can also provide additional vehicle and trailer information to help owners understand their setup, including vehicle mass and axle ratings. These features build on the trailering technology already available in GMC trucks, where drivers can monitor and configure various trailer-related functions through the vehicle.

The 2027 GMC Sierra 1500 therefore represents a significant change in philosophy as much as a redesign. GMC is not forcing every buyer toward the same engine or the same type of truck.

Someone primarily interested in maximum towing can choose the 402-horsepower 5.7-liter V8 and its 13,500-pound maximum towing capability. A driver looking for stronger gasoline performance can move to the 481-horsepower 6.6-liter V8 with 501 pound-feet of torque. Buyers who prioritize diesel torque, towing efficiency, and long-distance range can stay with the 3.0-liter diesel and potentially travel more than 900 miles between fuel stops when equipped with the larger tank.

At the same time, the Sierra is moving heavily into the digital age with its massive collection of displays, passenger entertainment screen, articulating center display, Super Cruise availability, new towing assistance features, and expanded connectivity.

Perhaps the most interesting part is that GMC has not completely abandoned traditional truck priorities in the process. There are still physical controls, serious towing numbers, specialized off-road hardware, large fuel tanks, and multiple engines designed for very different types of owners.

With a 481-horsepower V8 on one end, a 13,500-pound towing configuration on another, and a diesel capable of more than 900 miles of estimated range, the 2027 Sierra 1500 is trying to cover an unusually wide range of needs within a single truck family. For Sierra buyers, choosing the right engine may now be one of the most interesting parts of configuring the truck.