GM Targets Ford While Teasing Its New Duramax Diesel 8.3-Liter Engine Called ‘Mongoose’Car and DriverJack FitzgeraldMon, September 21, 2026 at 3:12 PM UTCAdd us on GoogleGM Teases New Diesel 8.3-Liter 'Mongoose' EngineGeneral MotorsGeneral Motors has teased a new Duramax diesel 8.3-liter engine that it has dubbed "Mongoose."The massive new powerplant will be available in Chevrolet and GMC's heavy-duty pickups.GM's teaser video took shots at the competition, showing a Mongoose attacking a Scorpion—Ford's internal codename for its Power Stroke diesel engine.The arms race between heavy-duty pickup-truck makers is alive and well, even as much of the auto industry focuses on electrifying its lineups. Still, Detroit's Big Three continue to push the limits of combustion engines, especially with their biggest trucks, and General Motors has just upped the ante one more time.In a new YouTube video, GM just announced a new Duramax diesel 8.3-liter engine bound for its heavy-duty pickups. Aside from the displacement, we don't have any engine specs yet, and we can't yet confirm its cylinder count. Still, we can be sure that the Mongoose is riddled with superlatives.AdvertisementAdvertisementHeck, GM is abundantly clear about targeting the competition. There's the name itself: Mongoose, which is a clear shot Ford's "Scorpion" 6.7-liter Power Stroke diesel, which powers the brand's heavy-duty trucks. And then there's the video, which shows a bow-tie-eyed Mongoose attacking and killing a Scorpion that just so happened to be walking in an oval.So while we don't know the high end of the Mongoose's stats, we can be sure of the low end. Considering that the Power Stroke generates 500 horsepower and 1200 pound-feet of torque, the Mongoose is sure to outdo those figures.When it arrives with the 2027 Chevy Silverado HD and 2027 GMC Sierra HD lineups, the Mongoose will supplant GM's current Duramax 6.6-liter V-8, which churns out 470 horsepower and 975 pound-feet of torque. Those might be respectable figures, but in the world of HD trucks, no one wants to be outdone by their rivals.➡️ Skip the lot. Let Car and Driver help you find your next car.Shop New Cars Shop Used CarsYou Might Also LikeGift Guide: Best Ride-On Electric Cars for KidsFuture Cars Worth Waiting For: 2025–2029