Review: The 2025 Ram 2500 Diesel Is A 25 MPG Heavy Hauler

By Gary Gastelu |

Jul 23, 2025

The big news from Ram this year is that the Hemi V8 engine is coming back to the Ram 1500 light duty pickup in a few months, but the old diesel six-cylinder is gone for good. If you want one of those, you’ll have to step up to a Ram 2500 or 3500 heavy duty truck.

The updated 2025 HDs are offered with the choice of a 6.4-liter V8 or a turbocharged 6.7-liter straight-six-cylinder built by Cummins. Cummins and Ram have a longstanding relationship, that was recently extended until at least 2030. The V8 is rated at 405 hp and 429 lb-ft, while the diesel cranks out 430 hp and 1,075 lb-ft.

The HD diesels have also switched from a six-speed to an 8-speed automatic transmission with the aim of improving their performance, fuel efficiency and refinement.

Pricing for the 2500 starts at $47,660 for a regular cab tradesman with an eight-foot bed. Above that is the Big Horn While the Laramie crew cab with a six-foot, four-inch bed that I tested is really the first trim that starts to get fancy and starts at $62,695, or $66,525 with four-wheel drive. That is until you add that diesel engine, which is a $12,595 option. That might sound exorbitant, but it’s on par with what Ford and GM charge for their diesels.

Pulling power doesn’t come cheap, and that’s what the diesel is all about. The 3500’s tow rating maxes out at 36,610 pounds while 2500s can two up to 20,000 pounds, depending on the configuration. The truck I tested gets close to that and has a payload rating of 2,244 pounds.

The Laramie features leather upholstery and a standard three-across split front bench seat with a center seat that can be folded down to serve as a console with storage. The cabin doesn’t feel commercial at all and comes with a digital instrument cluster and a large portrait-oriented touchscreen display for the infotainment system that is thoughtfully framed with buttons and knobs for the climate control and audio system, which is a nine-speaker Alpine with a subwoofer.

The 2500 is also available in a mega cab body style, but the crew cab is plenty roomy in both rows. The rear seat can be flipped up and has fold-out panels below it that create a flat load floor around the transmission hump.

The towing mirrors have flat and wide angle mirrors along with integrated spotlights, plus power fold and extension features. A trailer information section in the infotainment system can be programmed for several trailers of different lengths and track their milage. It can also be used too do a light check.

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The updated engine and transmission combination knocks more than a second off of the 2024 diesel’s 0-60 mph acceleration time to 6.9 seconds and improves the fuel economy. The EPA doesn’t rate heavy duty trucks, but in my real world testing the 2500 consistently delivered 25 mph on the highway and stayed in the high teens in combined driving, but not while towing or hauling.

The Laramie 4×4 isn’t outfitted as an off-road truck, but does have 9.3 inches of ground clearance under the axles, which is nearly two inches more than the two-wheel-drive models have.

On pavement, the ride quality is excellent and surely the best in class, thanks in part to the four-corner coil-spring suspension. The diesel is also whisper-quiet while cruising and the wind noise is very low for such a huge vehicle. The Ram 2500 Laramie is a long-hauler you won’t mind spending a long time in.