The GMC Sierra 1500 changes substantially for 2027. A new generation introduces two new V8 engines, more power from the TurboMax, a completely redesigned cabin, expanded digital displays and significant upgrades to both the AT4X and Denali Ultimate.
Those changes also create plenty of specific questions for truck shoppers. How much can the new Sierra tow? Which engine has the most torque? What equipment separates an AT4X from an AT4? How much technology is included in Denali Ultimate?
This guide answers those questions with a detailed look at the specifications and features of the 2027 GMC Sierra 1500.
1. What are the four engine options in the 2027 GMC Sierra 1500?
The 2027 Sierra offers four distinct engines:
| Engine | Horsepower | Torque |
|---|---|---|
| 2.7L TurboMax | 350 hp | 455 lb-ft |
| 3.0L Duramax Turbo-Diesel | 305 hp | 495 lb-ft |
| 5.7L V8 | 402 hp | 428 lb-ft |
| 6.6L V8 | 481 hp | 501 lb-ft |
The TurboMax has been upgraded for 2027, while the 5.7L and 6.6L are completely new sixth-generation Small Block V8 engines.
The Duramax 3.0L inline-six turbo-diesel remains part of the lineup for buyers who prefer diesel torque and long-distance capability.
2. What changed with the TurboMax engine for 2027?
The enhanced 2.7L TurboMax now develops 350 hp and 455 lb-ft of torque.
That represents an increase of 40 hp and 25 lb-ft compared with the previous version.
Mechanical revisions include a new turbocharger, upgraded fuel injection, improved thermal management and redesigned pistons. It is also now paired with a 10-speed automatic transmission.
Maximum Sierra towing capacity with the TurboMax reaches 4,264 kg, while maximum payload can reach approximately 1,048 kg.
3. How powerful is the new 5.7L V8?
The new sixth-generation 5.7L V8 produces 402 hp and 428 lb-ft of torque.
Although the 6.6L is more powerful, the 5.7L delivers the Sierra’s highest maximum towing capacity.
When the truck is properly configured, it can tow up to 6,123 kg, or 13,500 lb.
Maximum payload with the 5.7L can reach approximately 971 kg.
4. What are the specifications of the new 6.6L V8?
The new 6.6L V8 produces 481 hp and 501 lb-ft of torque.
That makes it the most powerful naturally aspirated V8 in its segment.
The engine is standard in the Sierra Denali Ultimate and can tow up to approximately 4,264 kg, depending on configuration.
Rather than being designed specifically to achieve the Sierra’s highest possible tow rating, the 6.6L emphasizes maximum horsepower, torque and overall performance.
5. How much can a 2027 GMC Sierra 1500 tow?
Maximum towing capacity varies substantially according to engine and configuration.
| Engine | Maximum Towing |
|---|---|
| TurboMax | 4,264 kg / 9,400 lb |
| 3.0L Duramax | 5,488 kg / 12,100 lb |
| 5.7L V8 | 6,123 kg / 13,500 lb |
| 6.6L V8 | 4,264 kg / 9,400 lb |
The 5.7L V8 provides the highest available tow rating.
These are maximum ratings. Cab configuration, drivetrain, installed equipment, passenger weight and cargo can all affect the towing capacity of an individual Sierra.
6. Which Sierra engine has the most torque?
The 6.6L V8 has the highest torque output at 501 lb-ft.
It is followed closely by the Duramax 3.0L turbo-diesel with 495 lb-ft.
The TurboMax develops 455 lb-ft, while the new 5.7L V8 produces 428 lb-ft.
This illustrates how differently the four engines are positioned. Engine displacement alone does not determine towing capacity, payload or the type of driving each powertrain is best suited to handle.
7. Does every 2027 Sierra use the same transmission?
Yes. Every available 2027 Sierra 1500 engine is paired with a 10-speed automatic transmission.
That includes the enhanced TurboMax.
A 10-speed transmission provides a broad range of ratios, allowing the powertrain to choose a suitable gear for conditions ranging from low-speed hauling to highway driving and towing.
8. Which versions of the 2027 GMC Sierra will be offered?
The Canadian lineup includes: Pro, Elevation, AT4, AT4X, Denali, and Denali Ultimate.
The range is structured around very different uses rather than simply progressively adding equipment.
Pro is oriented toward practical truck use, Elevation combines daily usability with distinctive styling, AT4 and AT4X progressively increase off-road capability, and Denali and Denali Ultimate focus more heavily on premium comfort and technology.
9. How is the new Sierra interior different?
Every 2027 Sierra trim receives a completely redesigned interior.
Changes include new dashboard architecture, revised materials and new colour combinations. Premium models offer real wood trim, while Denali Ultimate incorporates forged-wood accents.
An available panoramic sunroof is also offered.
A new MultiPro centre console can open to create an extended work surface while providing additional storage and access to available USB charging ports.
10. How many screens are available in the Sierra Denali Ultimate?
The Denali Ultimate can provide more than 60 inches of combined available digital display area.
The system includes:
- 16.3-inch infotainment display;
- 11.5-inch front passenger display;
- 12.2-inch Driver Information Centre;
- 15-inch multicolour Head-Up Display;
- 8.5-inch Rear Camera Mirror.
The centre screen can articulate and hides a storage compartment behind it.
The passenger display also has an articulating cover, allowing the presentation of the dashboard to change when the screen is not needed.
11. What audio system is available in Denali Ultimate?
A 16-speaker Bose Premium Series audio system is available.
Some of its speakers are integrated into the front head restraints, creating a more focused audio experience for front occupants.
It is one of several features that distinguish Denali Ultimate from more conventional full-size pickup interiors.
12. Can Super Cruise be used while towing with the Sierra?
Yes. Denali Ultimate includes a three-year subscription to Super Cruise driver assistance technology with trailering capability.
The system supports compatible hands-free driving on more than 965,000 km of compatible roads in Canada and the United States, including while towing under supported conditions.
Automatic Lane Change and Turn Signal Initiated Lane Change functionality are also supported when conditions permit.
13. What makes the 2027 Sierra AT4X more capable off-road?
The AT4X receives several substantial upgrades.
Key equipment includes:
- 35-inch Goodyear Wrangler Territory MT tires;
- 2-inch factory suspension lift;
- Multimatic dampers;
- New Multimatic Jounce Control Dampers;
- Front electronic locking differential;
- Rear electronic locking differential;
- Dedicated off-road hood;
- Redesigned front fascia.
The 35-inch tires are the largest factory-installed tires offered on a Sierra 1500.
14. Why are two locking differentials important on the Sierra AT4X?
Electronic locking differentials can mechanically help both wheels on an axle turn together when additional traction is required.
Because the AT4X has lockers at both the front and rear axles, it can maintain drive across all four wheels in situations where uneven terrain causes individual tires to lose traction.
They work alongside the truck’s selectable drive modes, tires and specialized suspension components.
15. Is there still an AEV Edition of the Sierra AT4X?
Yes. GMC continues to offer the AEV Edition for 2027.
It builds on the AT4X for buyers who want additional specialized equipment and protection for more demanding off-road use.
16. When does the redesigned 2027 GMC Sierra arrive?
The first 2027 GMC Sierra 1500 models are expected to arrive at Canadian GMC dealerships before the end of 2026.
The combination of new engines, a redesigned cabin, expanded technology and more specialized premium and off-road versions makes the 2027 Sierra a genuine new generation rather than a minor update.
