General Motors has officially confirmed the development of a new 8.3-liter Duramax turbodiesel V8 engine. The manufacturer has dubbed the unit Mongoose, a direct reference to its intent to compete with the 6.7-liter Power Stroke diesel engine from Ford, which is known internally as the Scorpion.
The new engine is scheduled to be installed in the refreshed 2027 Chevrolet Silverado HD and GMC Sierra HD pickup trucks. This represents a 26-percent increase in displacement compared to the current 6.6-liter Duramax engine, which produces 470 horsepower and 975 lb-ft of torque.
Technical specifications, including final horsepower, torque figures, towing capacity, and transmission details, have not yet been disclosed by the company. Pricing and specific model configurations for the upcoming trucks also remain unannounced.
It is currently unclear whether the 8.3-liter engine will serve as a complete replacement for the existing 6.6-liter Duramax or if it will be positioned as a higher-output alternative within the lineup. Further details regarding the rollout are expected at a later date.
