Is a 2018 Ram 2500 HD Cummins diesel more or less efficient at towing a 12,500 lbs trailer than a Ford Super Duty Power Stroke diesel? This is precisely the question we set out to answer. We loaded the CM Trailers 20-foot Cargo Mate trailer up to 12,500 pounds with water ballast and went on our standard “100-mile” highway fuel efficiency loop. We run this test at 70 mph on a relatively flat and empty stretch of Interstate I-76.
Ram uses an 68RFE 6-speed automatic transmission in their 2500 (3/4 ton) trucks, and the 6.7L Cummins I6 diesel is tuned to 370 hp and 800 lb-ft of torque. This is considerably less than the 440 hp and 925 lb-ft of torque that is coming from the Ford’s V8. Ford uses a heavy duty 6-speed automatic in their diesel-powered Super Duty trucks.
| 2018 Ram 2500 HD | 2017 Ford F250 SD | |
| Engine | 6.7 Cummins I6 | 6.7L Power Stroke V8 |
| Power | 370 hp @ 2,800 rpm | 440 hp @ 2,800 rpm |
| Torque | 800 lb-ft @ 1,600 rpm | 925 lb-ft @ 1,800 rpm |
| Rear axle ratio | 3.42 | 3.55 |
Get all of the details about the Ford F250 Power Stroke run. We also did a 0-60 MPH run in the Ford, and it was quick.
Perhaps, it’s no surprise that a straight-six turbo-diesel from Cummins that develops less power is more efficient on our highway loop than a turbo-diesel Power Stroke V8.
Check out all of the details in the video below.
