Video: How Far Can a Diesel and Electric Truck Tow an Identical Camper Trailer on One Fill-up?

The Hummer EV got 23.9 MPGe while towing this trailer.

gmc hummer ev ram hd 2500 cummins diesel camper towing comparison

How does the new GMC Hummer EV truck compare to a Ram HD 2500 Cummins truck when towing a 6,100 lbs camping toy-hauler trailer on one fill-up of energy or fuel? The heavy-duty Ram turbo-diesel is our towing machine benchmark for this test. The new electric Hummer is the challenger.

This review is packed with numbers so you can see exactly how efficient and capable these two powertrain technologies are.

GMC Hummer EVRam HD 2500
three electric motors (AWD)6.7L turbo-diesel I6 (4×4)
Power1,000 hp370 hp
Torque1,200 lb-ft 850 lb-ft
Curb Weight (as tested)9,400 lbs8,000 lbs
Max Payload (as tested)1,300 lbs2,000 lbs
Max Towing (as tested)7,500 lbs20,000 lbs
Max Range (no trailer)329 milesapprox. 600 miles

These two are in the “heavy-duty” truck category, but the Hummer EV’s capability rating are lower. The Hummer truck is more focused on off-road capabilities as a lifestyle vehicle. The Ram HD is a Big Horn trim level that is focused more on daily work.

We charged the Hummer EV to 100% and topped off the Ram’s diesel tank. We left Boulder, CO and headed towards Lake McConaughy in Nebraska – which is at least 215 mile away.

Spoiler Alert: here are the results. This table is using the following energy conversion factor: 1 gallon of Diesel#2 is equivalent to 37.95 kWh of energy.

GMC Hummer EVRam HD 2500
Energy onboard212.7 kWh31 gallons (or 1,176 kWh)
Miles w/ Trailer123.2 miles211.6 miles
Energy Used w/ Trailer195 kWh (or 5.1 gallons)21.76 gallons (or 825 kWh)
Energy Efficiency0.63 mi/kWh (or 23.9 MPG)9.7 MPG (or 0.25 mi/kWh)
Total Miles w/ Trailer*133* miles301* miles

*Total theoretical driving range with this trailer.

The results are very eye-opening. The all-electric Hummer truck would be able to pull this type of toy-hauler trailer approximately 133 miles on a full charge. The diesel Ram truck will do about 301 miles with an identical trailer.

On the flip side, the Hummer EV got 23.9 MPGe while towing this trailer. The Ram Cummins got a calculated 9.7 MPG.

The Hummer is using its energy more efficiently, but it cannot go anywhere as far with a trailer. The Hummer is about 2.5 times more efficient, but can go about 0.45 times the distance with a trailer.

There is also the time required to replenish the used energy. We saw a very fast 342 kW charging speed for the Hummer EV, but this is a peak charging speed. In reality, getting a meaningful and partial charge at a level 3 fast charger would require 30-40 minutes of time. Getting a full tank of diesel replenished in the Ram takes a matter of several minutes.

Enjoy the video below for all the details.