The “Mongoose” is General Motors’ new heavy-duty pickup-truck diesel engine. Scheduled to debut in the 2027 Chevrolet Silverado HD and GMC Sierra HD, the Mongoose is offered as an option to the standard 6.6-liter gasoline V8 powerplant. What is the Duramax “Mongoose” Diesel? Mongoose Internally designated LP6, the big  8.3-liter turbocharged V8 replaces the Duramax...