Diesel Dilemma: Navigating the Pros and Cons of Diesel Engines in the U.S.

As you celebrate America this July 4, give the following some thought. We are living through a diesel engine renaissance in the United States. More vehicles than ever before are being offered, or are going to be offered, with diesel engines due to their economy and the demand by the consumer—despite how increasingly difficult it is for a diesel engine to meet its NOx (Nitrogen Oxide) emissions controls.

But is everyone ready to pay for the increased cost of acquisition and maintenance that comes with this ignition-less pet? Do not get us wrong, we are all for the diesel revolution, but it is important to recognize why it might not always be the best choice.

Here we have a RAM Power Wagon for reference. The only engine available with it is the 6.4L “Apache” Hemi V-8, a medium-duty, two-valve OHV engine design with sixteen spark plugs and an output of 425 hp and 429 lb-ft of torque. Respectable numbers, right? It is beating out horsepower numbers (by nearly double) and coming close on torque of turbo-diesel engines of the early ‘00s. But with all that power and durability built in, people still look down at the Power Wagon for having a petrol power plant over the 6.7L Cummins engine and say that they would have bought a Power Wagon in an instant if it had come with a Cummins.

But why? The Cummins and its driveline weigh almost 1000 lbs more than the 6.4L, are incredibly complex with its turbocharging and direct injection systems, have higher maintenance costs, and the biggest issue of all, the massive intercooler system means that the 12,000lb Warn winch that comes standard on the Power Wagon would not be able to be used because of space restrictions. Further, the fuel economy gain that the diesel is not significant enough to be a viable measurement unless you are towing and willing to front the $9,000 investment of the diesel till you get your break-even return at 250,000 miles.

How is the fuel economy on the Ram Power Wagon 6.4L? Well, with no published numbers anywhere on the web and the EPA excluding the vehicle due to size and weight, the numbers will vary. However, we can say that our fuel economy is impressive for a 7000lb truck with a gas engine. It gets 12.5mpg city and 16.5mpg highway on 37×13.50R20 Falken Wildpeak MT’s mounted on 20×9.5 Trail Ready beadlocks. Not bad.