GM’s New 8.3L Duramax V8 Packs Enough Punch to Take Down Ford’s Top Spot
GM's new 8.3L Duramax V8 produces 555 hp and 1,230 lb-ft of torque, beating Ford's high-output Power Stroke on both figures.
Key Takeaways
- The new 8.3-liter Duramax produces 555 hp and 1,230 lb-ft of torque.
- GM replaces hydraulic steering and brake assist with electric systems.
- Maximum gooseneck towing rises to 38,000 pounds, still shy of Ford’s 40,000.
- The new diesel tops Ford’s 500-hp, 1,200-lb-ft Power Stroke.
- GM’s maximum gooseneck rating climbs from 36,000 to 38,000 pounds.
What’s Behind the New 8.3L Duramax V8?
The new turbodiesel V8 uses a compacted graphite iron block, a fully forged crankshaft and connecting rods, and forged steel pistons.
GM also specifies high-flow fuel injection, a variable-geometry turbocharger, and a compact, dual-stage air-to-water charge-cooling system.
An integrated intake and crankshaft isolation hardware are intended to tame noise and vibration.
How Does the New Diesel Compare to the Old One?
The new diesel replaces the familiar 6.6-liter Duramax, which offered 470 hp and 975 lb-ft in the 2026 Silverado HD.
That’s an increase of 85 hp and 255 lb-ft, or roughly 18 and 26 percent, respectively.
GM calls the 8.3-liter a clean-sheet, in-house design, rather than a development of an existing engine.
What About the Gas Engine?
Both the diesel and the updated gas V8 use GM’s Allison 10L1000 ten-speed automatic transmission.
The gas engine remains a 6.6-liter unit, but a new intake manifold, revised lubrication, an engine-mounted oil cooler, and updated emissions hardware bring it to 412 hp and 472 lb-ft.
What Are the Towing and Payload Capacities?
GM’s maximum gooseneck rating climbs from 36,000 to 38,000 pounds, with conventional towing rated up to 20,000 pounds.
The new diesel tops Ford’s 500-hp, 1,200-lb-ft Power Stroke, but Ford still advertises a 40,000-pound gooseneck maximum.
How Does the New Steering System Work?
GM is replacing its HD trucks’ hydraulic steering with rack-and-pinion electric power steering, claiming approximately 30 percent more steering output than the old gear.
The new hardware also allows steering and braking behavior to change with the drive mode.
Specifications
| Specification | Value |
|---|---|
| Engine | 8.3L Duramax V8 |
| Power | 555 hp |
| Torque | 1,230 lb-ft |
| Transmission | 10-speed automatic |
| Maximum gooseneck towing | 38,000 pounds |
| Conventional towing | 20,000 pounds |
Pros and Cons
Pros
- Increased power and torque
- Improved towing capacity
- New steering system
- Updated gas engine
Cons
- Still shy of Ford’s 40,000-pound gooseneck maximum
- No prices announced yet
- No detailed ratings by configuration
- No engine-speed figures for peak output
Frequently Asked Questions
Q: What is the new 8.3L Duramax V8 engine?
The new 8.3L Duramax V8 is a clean-sheet, in-house design that produces 555 hp and 1,230 lb-ft of torque.
Q: How does the new diesel compare to the old one?
The new diesel replaces the familiar 6.6-liter Duramax, which offered 470 hp and 975 lb-ft in the 2026 Silverado HD.
Q: What are the towing and payload capacities?
GM’s maximum gooseneck rating climbs from 36,000 to 38,000 pounds, with conventional towing rated up to 20,000 pounds.
