General Motors unveiled the specifications and business strategies underpinning its next generation engines slated for its 2027 Chevrolet Silverado and 2027 GMC Sierra pickup trucks.
Mark Dickens, executive chief engineer of GM’s full-size trucks and SUVs, told media at a Sept. 16 event at the Flint Engine Operations plant that each of the four engine types the company designed had a “clear role” in the company’s light-duty lineup.
“GM’s powertrain strategy is not about offering more engines simply to offer more engines,” Dickens said. “It’s about recognizing that truck customers use their vehicles differently, and giving each customer a powertrain that fits the way they work, tow, haul, commute, travel and play.”
Here’s what changes between the
four engine types:
L76 5.7 liter sixth-generation V-8

The smaller 5.7 liter next-generation V-8 delivers 402 horsepower and 428 pound-feet of torque.
Dickens said the team designed the engine for drivers who desire the “response and character of a naturally aspirated V-8 along with the towing and hauling capability expected with a full-size pickup.”
L78 6.6 liter sixth-generation V-8

Meanwhile, the 6.6 liter sixth-generation engine, with 481 hp and 501 pound-feet of torque, makes it “the most powerful naturally aspirated V-8 in the segment,” according to GM.
The engine provides “a stronger, more immediate response,” from the truck when accelerating or climbing with a trailer or other load.
“The 5.7 liter and the 6.6 liter are not simply larger versions of an existing engine,” Dickens said. “They’re an all-new-generation sixth small block architecture developed to meet future emission requirements with optimized fuel economies, CO₂ performance and power.”
Enhanced TurboMax engine

The 2.7 liter TurboMax underwent a “substantial upgrade” from the consumer’s perspective, Dickens said. The engine has a new turbocharger, fuel injection system, redesigned pistons and better thermal management. It is capable of generating 350 hp and 455 pound-feet of torque ― an improvement of 40 hp and 25 pound-feet of torque from the prior generation.
“Customers will feel this in the way the truck pulls away from a stop, responds to traffic and carries a load without needing hard work,” Dickens said. When paired with the 10 speed automatic transmission, he added: “It makes the delivery smooth and predictable … the overall result is a more responsive and refined TurboMax.”
Duramax 3.0 liter Turbo-Diesel

The 3.0 liter Duramax diesel, which in keeping with its previous generation, produces 305 hp and 495 pound-feet of torque.
The company boasts that when paired with the 34 gallon gas tank, vehicles equipped with the diesel engine can reach over 900 miles ― the distance from Flint to Savannah, Georgia ― without stopping for fuel.
“These four engines are not variations of the same answer. Each use a different combination of architecture, torque, delivery, airflow, thermal management fuel system strategy and calibration to meet distinct customer needs,” Dickens said. “The engineering work is to make those differences meaningful from behind the wheel.”
Jackie Charniga covers General Motors for the Free Press. Reach her at jcharniga@freepress.com.
This article originally appeared on Detroit Free Press: GM’s next-generation pickup engines come in 4 types for a reason













