General Motors has finally pulled the cover off its two new V8 engines for its next-generation full-size pickups. The 2027 Chevrolet Silverado 1500 and GMC Sierra 1500 will get two versions of GM's sixth-generation Small-Block V8: a new 5.7-liter L76 and a 6.6-liter L78.
We got our first look at these engines when GM debuted its redesigned pickups earlier this year, but the automaker hadn't revealed all the details. Now we know exactly what these V8s bring to the table, including higher displacement, more power, and some significant changes under the hood.
New 5.7-Liter V8: Better Than Its Predecessor
The new 5.7-liter V8 produces 402 horsepower and 428 pound-feet of torque, effectively replacing GM's outgoing 5.3-liter V8. GM increased displacement by lengthening the engine's stroke by 6.0 millimeters, bringing total displacement to 350 cubic inches.
The result is 47 more horsepower and 45 more lb-ft of torque than the 5.3-liter it replaces.
GM also gave the new V8 a higher compression ratio, larger throttle bodies, and redesigned intake manifolds with tuned runners to improve airflow. Like the other engines in GM's sixth-generation Small Block family, it uses both direct and port fuel injection.
And despite being the smaller of the two new V8s, the 5.7-liter is actually the one to get if towing is your priority. Properly equipped, the 2027 Silverado 1500 can tow up to 13,700 pounds with the 5.7-liter, while the equivalent Sierra 1500 is rated for up to 13,500 pounds.
New 6.6-Liter V8: The Range-Topping Option
The new 6.6-liter L78 replaces the outgoing 6.2-liter V8 and bumps up the output considerably. The 400-cubic-inch engine makes 481 hp and 501 lb-ft of torque—61 more horsepower and 41 more lb-ft than the engine it replaces.
That extra displacement and power don't translate into a higher tow rating, though.
GM rates the 6.6-liter for up to 9,700 pounds in the Silverado and 9,400 pounds in the Sierra. Instead, the bigger V8 is aimed more at buyers who want maximum performance and higher-end equipment.
It's also worth pointing out that the L78 isn't quite the same engine as the 6.7-liter LS6 used in the 2027 Corvette. Yes, all three engines belong to GM's sixth-generation Small Block family and share the same 4.40-inch bore spacing, but the truck engines are specifically engineered for things like towing, hauling, and off-road driving.
The Numbers
| Horsepower | Torque | Max Towing | Max Payload | |
| L76 5.7L V8 | 402 | 428 | 13,700 (Silverado) / 13,500 lbs (Sierra) | 2,170 (Silverado) / 2,140 lbs (Sierra) |
| L78 6.6L V8 | 481 | 501 | 9,700 (Silverado) / 9,400 lbs (Sierra) | 1,510 (Silverado) / 1,450 lbs (Sierra) |
The new V8s will initially be built at GM's Flint Engine Operations, with additional production capacity planned at Tonawanda Propulsion in New York and St. Catharines Propulsion in Canada. GM says the engines will be available when the next-generation Silverado 1500 and Sierra 1500 launch later this year.
Motor1's Take: GM clearly isn't ready to give up on the V8—and that's great news. The 5.7-liter gets a healthy bump in power while offering higher towing capacity, and the 6.6-liter is aimed at buyers who want more performance.
