General Motors just announced a new Duramax diesel engine and named it after the animal that kills Ford’s engine.
GM dropped a YouTube video this week. No press release, no technical briefing — just a cartoon mongoose hunting a scorpion around an oval track until the scorpion is dead. Then the name: Mongoose. Ford’s Power Stroke diesel has carried the Scorpion codename for years. The oval in the video matches Ford’s badge. GM’s marketing team had a good week. The engine is an 8.3-liter V-8 Duramax diesel going into the 2027 Silverado HD and Sierra HD — and whatever the numbers turn out to be, GM clearly thinks it has Ford beaten before the spec sheet even drops.
What the Mongoose Duramax Diesel Is Replacing
The current Duramax diesel — 470 horsepower, 975 lb-ft of torque — has been in GM’s HD trucks for years. Good engine. Not good enough anymore. Contractors who tow heavy trailers, farmers running loaded grain haulers, fleet buyers who compare spec sheets before signing — they all know Ford’s numbers are higher. GM knows it too.
The Mongoose Duramax diesel at 8.3 liters is significantly larger than both. GM hasn’t released power figures yet but the displacement alone tells you which direction this is going. An 8.3-liter diesel V-8 in a heavy-duty pickup is the largest diesel engine displacement in the segment by a meaningful margin. Whatever the numbers turn out to be, they will exceed what the Power Stroke currently puts out — GM made that expectation clear by naming the engine after the animal that kills Ford’s codename creature.
Why 8.3 Liters Is a Big Deal
Displacement is just the total size of all the engine’s cylinders combined. A bigger number means more space for air and fuel to burn on each stroke of the engine. More burning means more force pushing down on the pistons. In a heavy-duty truck that’s hauling a loaded horse trailer or a construction equipment flatbed, that force is the difference between the engine working comfortably and the engine working at its limit.
Going from 6.6 liters to 8.3 liters is not a small jump. That’s 1.7 liters of extra displacement — roughly the size of a small car engine added on top of what GM already had.
The HD Truck Diesel Wars
A Silverado 2500 costs $50,000 minimum. People who spend that kind of money on a truck have a reason — a boat to tow, a trailer to pull, a business that depends on it. The diesel engine spec is what they look at first. Not the screen size. Not the driver assist features.
GM, Ford and Ram have been trading punches on HD diesel numbers for years. Every new generation one of them comes out ahead and the others have to respond. Ford moved ahead on torque. Ram closed the gap on its side. GM is last in that fight right now. The Mongoose Duramax diesel is how they get back in front.
What GM Has Confirmed and What’s Still Missing
Engine name — Mongoose. Displacement — 8.3-liter V-8. Trucks — 2027 Silverado HD and Sierra HD. That’s everything GM put out. Horsepower, torque, towing capacity and fuel economy figures haven’t been released yet. Those come when the trucks get closer to going on sale.
What can be said with reasonable confidence — the Mongoose Duramax diesel will exceed 500 horsepower and 1,200 pound-feet of torque. GM would not have teased this engine with a video directly attacking Ford’s numbers if the Mongoose wasn’t going to beat them.
FAQ
What is the GM Mongoose engine?
8.3-liter V-8 Duramax diesel. Lands in the 2027 Silverado HD and Sierra HD. No other HD pickup truck comes with a diesel this big.
Why did GM name it Mongoose?
Inside Ford, the Power Stroke diesel is known as the Scorpion. GM picked the one animal that hunts and kills scorpions. Then made a YouTube video about it.
How big is the Mongoose Duramax diesel?
8.3 liters. Current Duramax — 6.6 liters. Ford Power Stroke — 6.7 liters. Mongoose — 8.3 liters. That’s not a small step up.
What engine is the Mongoose replacing?
The 6.6-liter Duramax V-8 that’s been under the hood of GM’s HD trucks. 470 horsepower, 975 lb-ft of torque. The Mongoose is next.
Will the Mongoose beat Ford’s Power Stroke?
GM hasn’t released the numbers yet. Ford’s Power Stroke sits at 500 horsepower and 1,200 lb-ft of torque right now. An 8.3-liter diesel going up against a 6.7-liter rival — the Mongoose will beat those figures. GM wouldn’t have made that video if it didn’t.
When does the Mongoose engine arrive?
2027 Silverado HD and Sierra HD get it first. GM hasn’t locked in an on-sale date yet.
