The shooters at KGP Photography caught GM engineers testing several prototypes outfitted with an upgraded version of its Duramax Turbo-Diesel V8 engine. Performance specifications are unavailable at this time, but the goal must certainly be to bump the current 6.6L Duramax Turbo-Diesel's horsepower, torque and towing capacity to counter Ford's recently upgraded 6.7L Powerstroke V8 Turbo-Diesel. Ford's revamped 6.7L Diesel currently outguns GM's 6.6L units; the Ford generates 440 hp and 860 lb.-ft. of torque vs. GM's 397 hp and 760 lb.-ft. of torque. It's unknown exactly what internal changes are in play on these latest GMC and Chevy HD prototypes, although sources have reported that a more potent turbo and software upgrades are on tap for the ’16 model year. This fits perfectly with the evidence now spotted undergoing severe hot-weather testing in the California desert.
Deeper Breathing to Add Power
Part of GM's strategy is to feed more air into the engine via a new functional hood air intake designed into the truck's redesigned hoods. The new air duct sits prominently near the leading edge of the hood; the GMC gets a circular mesh intake grille while the Chevy appears to get a diamond-shaped interweaving mesh grille insert.
Definitely a Diesel
You may be wondering how the shooters can be sure that these prototypes were powered by GM's Duramax Turbo-Diesel engines. Here's how: They caught some of the prototypes tanking up and it was definitely diesel being dispensed into the truck. They also managed to zoom in tight on the fuel door, and it read "Ultra Low Sulfur Diesel Fuel Only." It's also worth noting that the test group had a Ford F-350 on hand as a benchmark vehicle, fitted with the 6.7L PowerStroke Turbo-Diesel V8.
More changes may ultimately be in store for GM's fullsize trucks, with some additional, modest changes to the truck's front fascias joining the redesigned hood spotted on these prototypes.
Photo credit: KGP Photography