Owner Review: Big Block GM Gas V8 vs Dodge Ram Cummins Diesel – Road Trip Towing MPG Comparison

Dan drove about 1,500 miles with a trailer in each truck.

You will not find any HD pickup truck comparison like this anywhere else!

This is a direct cross-country towing comparison between a 1992 Chevy big-block gas V8 truck and a 1994 Dodge Ram Cummins I6 turbo-diesel. Both trucks are well used. Both are towing the same identical trailer that weighs about 6,000 lbs. There is the same driver behind the wheel – it’s our friend, Dan Atkinson. Dan drove each truck close to 1,500 miles, the Dodge Ram went westbound, the Chevy K3500 did the return eastbound journey. Dan checked all fuel usage at the pump while he filled up and topped off the trucks. Here are all the details! 

Dan is a professional semi-truck driver. He is no stranger to truck stops and making long-haul towing trips. Dan maintained 65 MPH on both legs of this trip using his GPS navigation system. Why 65 MPH? Driving old pickup trucks at this speed increases the safety margin and increases the potential fuel economy. When the speed increases – the wind resistance causes the fuel efficiency to plummet. 

1994 dodge ram 1500 dan atkinson

Dan is towing his beloved Ford F-series we call “Six Shooter”. TFL originally purchased this truck as a parts truck, but it refuses to die. Dan and David turned it into a “Redneck Wrecker” truck to help Dan with his other projects. The trailer with the Ford on it weighs around 6,000 lbs, but I do not have an exact weight.

1994 Dodge Ram HD Diesel

This is a heavily used heavy-duty truck with over 349,000 miles on the odometer. Its nickname is “Redrum”. It was a daily work truck until Dan purchased it several years ago. It’s equipped with a 5.9L Cummins I6 turbo-diesel and a 4-speed automatic transmission. When new, this diesel was rated at 160 hp and 400 lb-ft of torque. It is a 2WD truck and has a few mechanical and cosmetic issues. The transmission is slipping, the speedometer does not work, and the dash is broken into several pieces (which is very typical for a 2nd-generation Ram truck of this era). 

This Dodge is rolling on 265/75R16 tires and it’s equipped with a 3.54 rear axle ratio.

After all 1,460 miles were said and done, Dan used 104.208 gallons of diesel for a total average of 14.01 MPG. This is impressive with everything considered.

Since we are planning to do many EV pickup truck towing tests soon, I will add this gallon to kWh conversion here. According to this conversion table, 1 gallon of diesel is equivalent to 37.95 kWh of energy. It means Dan used approximately 3,954.69 kWh to make this trip.

1992 Chevy K3500 HD Gas

You may recognize this pickup truck as “Powder Keg”. This truck used to belong to our friend – David Morrow. After some dealing, this big-block gas V8 truck now belongs to Dan. This is why he is driving it back to Georgia as a part of this cross-country adventure.

This Chevy was in fairly rough shape when David purchased it about a year ago, but it had very good bones. The 454 cubic-inch V8, the manual transmission behind it, and the 4×4 system are in very good working order. When new this big V8 engine was rated at 230 hp and 380 lb-ft of torque. David gave the truck a thorough makeover. He replaced a damaged driver’s door, repainted the exterior, installed many new trim pieces, and cleaned up the interior in a very significant way.

The Chevy is rolling on 285/75R16 tires and the rear axle ratio is 4.10.

On the way back out east, Dan tracked a slightly longer route (although the main part of the trip followed the same interstates and highways). Dan went 1,549 miles and used 150.612 gallons of gasoline. This works out to approximately 10.285 MPG.

Using the same gallon to kWh conversion table, 1 gallon of gasoline is equivalent to 33 kWh. Dan used approximately 4,970.19 kWh to make the trip in the gasoline-powered truck.

Indeed, this is not a huge surprise, a turbo-diesel pickup is better for towing a trailer over the long haul. Check out the Powder Keg video below.