The 6.6L is the more powerful gas V8, but the 5.7L has the higher available trailer rating in the 2027 GMC Sierra 1500. Choose the job first: do you want more power for everyday driving, or a particular cab and trailering combination?
| 2027 Sierra 1500 gas V8 | Horsepower | Torque | Highest GMC trailer rating |
|---|---|---|---|
| 5.7L | 402 hp | 428 lb-ft | 13,500 lb: Double Cab 4WD with Max Trailering |
| 6.6L | 481 hp | 501 lb-ft | 9,400 lb: Crew Cab 4WD |
Why the bigger V8 does not win both columns
Horsepower measures engine output. A tow rating applies to the complete truck. GMC lists the 6.6L light-duty V8 with a four-wheel-drive Crew Cab; the highest-rated 5.7L uses a different cab and the Max Trailering Package. If you need a Crew Cab, compare that body style on both sides: GMC lists up to 13,300 lb for the properly equipped 5.7L Crew Cab 4WD.
Which should you ask Circle to find?
For a family camper, send its loaded weight, measured tongue weight and the people and supplies riding in the truck. If you rarely tow and mainly want the stronger engine, ask to compare the response of both V8s on the same route. An engine badge will not tell you the payload remaining after passengers, cargo and hitch equipment are aboard.
These figures apply to the Sierra 1500. The 6.6L gas engine and Duramax diesel offered in Sierra HD trucks have separate specifications.
Compare V8 configurations in Highland
View current Sierra 1500 trucks Ask Circle about a 2027 configuration
Circle Buick GMC is at 2440 45th Street, Highland, IN. Listings can include other model years. Confirm the truck’s model year, equipment and availability before your visit.