For the first time in its storied history, the formidable Ram Power Wagon is set to receive a diesel engine option. Revealed for the 2027 model year, this iconic off-road beast can now be outfitted with the potent 6.7-liter Cummins High-Output turbo-diesel inline-six. This significant powertrain addition promises a substantial leap in capability, delivering an impressive 430 horsepower and a colossal 1,075 pound-feet of torque. Power is managed by a TorqueFlite HD eight-speed automatic transmission, sending it to all four wheels.

The introduction of the diesel variant, however, comes with a considerable weight increase. The massive cast-iron engine block and heavy-duty components push the 2027 Ram 2500 Power Wagon Diesel to a curb weight of 8,300 pounds. Despite the added heft, the diesel Power Wagon can achieve 0-60 mph and has a top speed of 105 mph. Orders are currently open, with these diesel-powered trucks expected to hit dealerships in late 2026. Starting at $89,560, this new diesel model marks the most expensive Power Wagon ever offered.

This new diesel offering prompts a direct comparison with the established HEMI-powered Ram 2500. While the diesel boasts immense torque, the HEMI-equipped truck, in its lightest configuration, weighs significantly less at 6,066 pounds. The 6.4-liter HEMI V8 engine within this truck produces 405 horsepower and 429 pound-feet of torque. This HEMI variant offers substantial towing and payload capacities, rated at 17,750 pounds and 4,580 pounds, respectively.

In a series of tests conducted by The Fast Lane Truck, both the diesel and HEMI Power Wagons, along with a Jeep Wrangler 392, were put through their paces. In an initial standing start acceleration test with traction control off, the diesel Power Wagon surprised by launching like a sports car, while the HEMI truck struggled with wheel spin. This initial victory for the diesel, attributed to its massive torque, set the stage for further comparison. A subsequent roll race, initiated at 30 mph, saw the HEMI gain an initial advantage, but the diesel eventually pulled ahead, overcoming its weight disadvantage to claim victory.

The Jeep Wrangler 392, equipped with the same 6.4-liter HEMI V8 found in the Ram 2500 but in a much lighter package weighing 5,103 pounds, was also part of the comparison. This V8 powerhouse generates 477 horsepower and 470 pound-feet of torque, propelling the Wrangler from 0-60 mph in a swift 4.5 seconds and reaching a top speed of 112 mph. While its performance figures are impressive, its role in this specific comparison highlights the different strengths and target audiences for each of these potent vehicles.