All-New 8.3-Liter Duramax® Mongoose Engine Overview
Massachusetts GMC drivers seeking ultimate power and innovation will find both in the 2027 Sierra HD and its all-new 8.3-liter Duramax® Turbo-Diesel V8 "Mongoose" engine. Engineered for heavy-duty demands, the Duramax® Mongoose delivers unparalleled horsepower, torque and advanced technology for tackling the toughest jobs and terrain.
Our GMC dealership near Fall River can help you discover how this next-generation diesel engine sets a new standard for performance, towing and control in the heavy-duty truck segment.
What Is the New Duramax® Mongoose Engine?
Available on the new GMC Sierra HD in Raynham, the 8.3-liter Duramax® Turbo-Diesel V8 is engineered from the ground up for drivers who demand relentless strength, durability and advanced diesel performance. The Mongoose engine sets a new benchmark for heavy-duty full-size trucks, offering best-in-class power and next-level towing capability on 2027 Sierra HD models.
8.3-Liter Duramax® Turbo-Diesel V8 Engine Specs & Highlights
The 8.3-liter Duramax® Turbo-Diesel V8 engine delivers incredible performance to help Massachusetts GMC fans conquer everything on their agenda. Performance highlights include:
- 555 horsepower
- 1,230 lb-ft of torque
- 20,000-lb. max conventional towing capacity
- 38,000-lb. max gooseneck towing capacity
- 10-speed Allison® transmission
Duramax® Mongoose Engine Performance Features
- All-new heavy-duty diesel engine architecture
- Compacted graphite iron cylinder block, fully forged crankshaft, steel connecting rods and pistons deliver exceptional strength and long-term durability under the harshest workloads.
- Segment-first rack-and-pinion Electric Power Steering
- Delivers about 30% more steering output than previous hydraulic systems for better maneuverability when towing or hauling heavy loads.
- More precise, consistent steering feel with reduced kickback on highways, jobsites and rough terrain.
- Quieter, lower-maintenance design eliminates traditional hydraulic components while enhancing durability and protection against corrosion and impacts.
- Electronic brake-boost system
- First-ever electronic braking system for a heavy-duty pickup delivers stronger, more consistent stopping power and control.
- Large 14.6-inch front rotors, upgraded calipers and rear hardware boost braking performance, pedal stiffness and confidence even when towing big trailers.
- Smarter braking integration supports advanced driver-assistance features and helps reduce system complexity and maintenance.
- Advanced cooling and turbocharging systems
- Dual-stage air-to-water charge cooling system and high-efficiency variable-geometry turbocharger keep performance consistent during heavy towing and working in extreme conditions.
- 10-speed Allison® automatic transmission
- Advanced shift logic helps ensure optimal power delivery, smoother acceleration and better grade performance when hauling or towing.
- Integrated diesel system engineered as a complete package
- Enhanced exhaust braking and aftertreatment layout boost long-term performance, regeneration function and confidence for demanding towing and long-distance hauling.
- Versatile drive modes for every scenario
- Normal, Tow/Haul, Off-Road and New Terrain Modes let you tailor powertrain, steering, braking and chassis systems for the task at hand, whether it's commuting, heavy towing or navigating technical off-road trails.
- Integrated trailer technology
- Improved trailer integration and technology help handle the most demanding jobs with enhanced stability, safety and confidence.
New GMC Sierra HD Trucks Near Me
Discover how the all-new 8.3-liter Duramax® Mongoose engine can transform your workday and bring new capability to every challenge you face. Whether you're tackling demanding jobsites, hauling heavy loads or exploring new terrain, the 2027 GMC Sierra HD with the Mongoose engine is engineered to exceed expectations in every way.
Experience the difference that class-leading power and innovation make -- contact Mastria GMC in Raynham today and get started on your next chapter of heavy-duty performance!
8.3-Liter Duramax® Mongoose Engine FAQs
How much can the 8.3-liter Duramax® Mongoose engine tow?
When properly equipped, the engine delivers up to 20,000 pounds of conventional towing and up to 38,000 pounds of max gooseneck towing.
What transmission is paired with the Duramax® Mongoose engine?
This engine is matched with a 10-speed Allison® automatic transmission featuring advanced shift logic for greater control and efficiency.
What makes the Mongoose engine more durable?
The engine uses a compacted graphite iron block, fully forged crankshaft, steel connecting rods and pistons for strength and longevity under extreme conditions.
Are there any new technologies in the Sierra HD with the Mongoose engine?
Yes. Segment-first electric power steering, electronic brake-boost system and advanced drive modes enhance control, safety and performance for all heavy-duty scenarios.