It’s time to put some miles on the new 2025 Ram HD Cummins turbo-diesel. The engine is updated. It makes more power, and it has a new 8-speed ZF Powerline automatic transmission. The new Cummins should be significantly more efficient than before. How does it compare to a new 2025 Chevy Silverado HD Duramax V8? Let’s dig in!
We take a 2025 Ram HD 2500 crew cab 4×4 Rebel and a 2025 Chevy Silverado HD 2500 crew cab 4×4 Trail Boss on a road trip from Moab, Utah back to our home state of Colorado. We aim to compare these two on a 360 mile journey, but everything does not go to plan.
Another very cool part of the trip is a dog food delivery for pets in need. I take around 1,000 pounds of dog food that is donated by Bark Co, loaded inside the Ram HD Rebel’s bed to Best Friends Animal Sanctuary in Utah.
The road trip plan is simple. Top off the diesel in Moab, Utah and follow the interstate 70 route to Golden, Colorado. We did exactly that, but a heavy snow storm closed the Vail Pass section of the highway. We had to find an alternate route that added about an hour to our trip. In the end, we went 318.5 miles in both trucks (driving one behind the other).
| 2025 Ram HD | 2025 Chevy Silverado HD | |
| Engine | 6.7L Cummins I6 | 6.6L Duramax V8 |
| Power | 430 hp @ 2,800 rpm | 470 hp @ 2,800 rpm |
| Torque | 1,075 lb-ft @ 1,800 rpm | 975 lb-ft @ 1,600 rpm |
| Transmission | 8-sp ZF Auto | 10-sp GM/Allison Auto |
| Rear Axle Ratio | 3.42-to-1 | 3.42-to-1 |
| Odo. Miles | 2,000 mi | 4,400 mi |
After the 318.5 mile journey, we got the following results. The Duramax inside the Chevy Silverado HD registered 18.2 MPG at the pump. The new Cummins / ZF combination in the Ram HD delivered 17.3 MPG. It’s a surprise. I expected a better result from the Ram truck. There are some other factors we cannot control. For example, these trucks can run a region cycle to clear the Diesel Particulate Filter (DPF) at any time. The fact that we are driving a longer distance to try to counteract this.
Please join Roman and I in the video below. You can see some happy puppies.
