A Guide to Diesel Vehicles

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Even after a global fraud scandal and a growing interest in battery electric cars, some vehicle buyers in America are still keen on diesel engines for their trucks and SUVs. Diesel vehicles remain a good choice for certain buyers. They are inherently more fuel-efficient under many driving conditions, and they can offer far greater driving range and tackle interstate trips for as long as you and your suffering bladder can hold on.

If you're wondering where all the diesel cars went, it's likely due to dwindling sales numbers for the automakers that still sold them after the "Dieselgate" scandal that came to light in 2015. The simplest version of what happened is that Volkswagen vehicles were found to deliberately emit more than the legal emissions limit during actual driving, while emitting below the legal limit while being tested for emissions. When the dust settled, massive fines were given out, and consumers were left with fewer diesel vehicle options as Volkswagen, Audi, and Porshe stopped selling their diesel models.

Now, the only diesel vehicles offered in the U.S. market are pickups, SUVs, and cargo vans aimed squarely at the commercial vehicle market.

The "How" on Diesels

First, let's get into what diesel vehicles are. The diesel engine has no spark plugs to ignite the mixture of fuel and air introduced to the engine. Rather, very high compression causes that combustion, which makes it more efficient and thrifty with fuel than a gas engine. The trade-offs, though, are that diesels are slightly louder because of that high compression and the engine's heavier internal components. Diesel emissions are harder to scrub clean to comply with pollution standards, but the old days of diesel exhaust soot fouling the air are gone. (If you do see a modern diesel vehicle puffing out black smoke, it's likely been tampered with to produce more power, with many of the emissions components removed or bypassed—it's also highly illegal in most areas).

For people who must tow heavy equipment, a diesel engine can be a great option. Private individuals in the excavation business, landscapers, home builders, and even folks who tow race cars rely on diesels in light-, medium-, and heavy-duty pickups. There's a reason the trucking industry still employs diesels in big rig trailers. Effortless power (really, torque) at low engine speeds and greater inherent efficiency are still the calling cards of the diesel engine.

Running Costs of Diesel Vehicles

Many years ago, diesel fuel was always less expensive than gasoline, but those days are largely gone. The cost of diesel fuel varies across the U.S., with the West Coast states and especially California having the highest prices. Today, the diesel/gas price relationship fluctuates as either one could be more expensive.

Diesels have traditionally been more durable and reliable than gasoline engines, requiring less frequent and less involved regular maintenance. But with the durability improvement in modern gas engines and the much higher power output of modern diesel vehicles—plus their exhaust after-treatment systems to help them run more cleanly—the difference between the two in this regard has diminished somewhat.

A quick look at current prices published by the government as of early December 2021 shows diesel at an average of $4.79 (all figures per gallon) in California, where gasoline is slightly less, at $4.62. The same study shows the U.S. states (less California) at an average of $3.34 versus $3.67 for diesel in California. However, even with those price differences, if you drive enough over the course of a year, the better economy of a diesel engine may make sense for you.

Calculating the Benefits

Generally speaking, diesel vehicles are about 29% more fuel-efficient on the highway and about 24% more efficient in the city. But if you want to take a more scientific approach to understand exactly what the differences will be over time and for the different fuel and efficiencies, use the U.S. government's nifty little annual fuel cost calculator to scope out your specific situation.

Let's look at the numbers generated in this manner for a 2022 Chevy Tahoe LT large SUV in both standard 5.3L gas engine and the 3.0L diesel option. Using a 50% split in city versus highway driving, plus the above 49-state fuel cost averages and a total yearly mileage of 15,000, shows that the diesel option saves $539 per year. This is despite the higher fuel cost. However, that does not reflect the additional cost of the diesel option itself, which is about $1,000 in the Tahoe's case. So, to recover that cost, you'd have to drive it for two years just to break even on the price difference. This still might make sense for you if you plan to keep the car for much longer. It will save you $539 per year for every year you own it, and at the 10-year mark, you'll be about $4,390 ahead in running costs versus the gasoline Tahoe.

Finding a Diesel Vehicle

Now comes the big question: Which trucks and SUVs offer a diesel engine today? There are 15 total available, but three of those are cargo vans meant for delivery services and commercial sales. Seven are pickups, and five are SUVs of varied sorts, but no traditional passenger cars are offered with diesel power in the U.S. The available vehicles include:

• Cadillac Escalade SUV

• Chevrolet Colorado pickup

• Chevrolet Silverado pickup

• Chevrolet Express van

• Chevrolet Tahoe SUV

• Chevrolet Suburban SUV

• Ford Transit van

• Ford F-Series pickup

• GMC Canyon pickup

• GMC Sierra pickup

• GMC Yukon SUV

• Jeep Wrangler SUV

• Jeep Gladiator pickup

• Mercedes-Benz Sprinter van

• Ram 1500 pickup

For sure, the incentive in the total cost of ownership of a diesel vehicle over one powered by gasoline in the past five or so years has diminished. And battery electrics have been grabbing most of the headlines. But the diesel engine may still offer better value and equal or greater performance for certain buyers who travel long distances or who need to tow trailers or equipment. For these folks, the diesel vehicle isn't dead. At least not yet.