General Motors is currently hard at work on its next-generation full-size, heavy-duty trucks – the 2500HD and 3500HD versions of Chevy’s 2020 Silverado and GMC’s 2020 Sierra. And now, GM Authority has discovered that these future GM HD trucks – which we have seen undergoing testing many times before – will introduce an all-new eight-cylinder gasoline engine.
High Displacement Gasoline V8
According to sources familiar with the automaker’s plans, the 2020 model year heavy duty GM trucks will utilize a new gasoline V8 engine displacing 6.6 liters. The motor will make around 400 horsepower and 450 pound-feet of torque – representing notable improvements of 40 horsepower and 70 pound-feet of torque – over the Vortec 6.0L V8 L96 that currently serves as the base engine in the current Silverado HD and Sierra HD.
|Current 6.0L V8 L96||Expected 6.6L V8 LXX|
The 6.0L L96 motor used currently is a rather old powerplant that traces its roots back to the mid-1990s, though it did receive an update in 2010. The eight-banger makes 360 horsepower and 380 pound-feet of torque.
Notably, the L96 is E85/FlexFuel capable and features Variable Valve Timing (VVT) and Sequential Fuel Injection (SFI, otherwise known as port fuel injection). That is to say that it does not have the latest internal combustion engine technologies such as direct injection, Cylinder Deactivation (in either AFM or DFM guise), or a low-friction valvetrain. By comparison, the new 6.6L unit is expected to adopt these technologies.
Testing By Navistar
Sources tell us that GM has almost completed development work on the new 6.6L gasoline engine for its future GM HD trucks, and that the engine is currently undergoing testing by Navistar, which is GM’s partner in developing and building the new Silverado Medium Duty Truck line – the Silverado 4500HD, Silverado 5500HD, and Silverado 6500HD.
This data point is particularly interesting, since it suggests that the new 6.6L engine will not only be used in the future GM HD trucks and in the 2020 Silverado Medium Duty, along with its equivalent from Navistar’s International Trucks brand.
Duramax Diesel V8
While the upcoming, 2020 GM HD trucks will feature an all-new gasoline engine, the diesel engine will remain the same – in the form of the 6.6L Duramax Diesel L5P making 445 horsepower and 910 pound-feet of torque.
The Duramax engine was introduced for the 2017 model year. As such, it is still considered a rather new powerplant that is still highly competitive against the PowerStroke V8 Diesel in the Ford F-Series Super Duty as well as the Cummins I6 in the Ram Heavy Duty.
Both, the new 6.6L gasoline engine and carry-over 6.6L Duramax Diesel are expected to be mated to new transmissions for the 2020 GM HD trucks.
However, we have received mixed reports on what form the transmissions will take, so we will refrain from publishing anything on them at this time.
About Future HD GM Trucks
The new trucks will ride on a more robust version of the new GM T1 platform introduced by Chevy’s 2019 Silverado 1500 and GMC’s 2019 Sierra 1500. Expect the new HD trucks to adopt an all-new exterior design similar to their respective light duty variants, while growing in size, shedding weight, improving capability, and having more comfort and convenience features, especially when it comes to towing technologies. An expanded model range consisting of Silverado Trail Boss and Sierra AT4 models is also expected.
The interiors will be redesigned and the cabs are expected to grow bigger for more interior room. However, as with the 2019 Silverado 1500 and 2019 Sierra 1500 models, they are not expected to stray too far from the design of current models.
Expect a launch in the third quarter of 2019 for the 2020 model year.