| Last updated November, 2026
For most used car buyers, a gas engine makes more sense: it costs less up front, handles short trips and city driving better, and has simpler, cheaper emissions equipment. A diesel makes sense if you tow heavy loads or drive a lot of highway miles. Diesels typically deliver better fuel economy and much more low-end torque, which pays off when you're pulling a camper or boat or covering long distances. Most used diesels today are pickups and full-size SUVs.
Diesel engines have a loyal following, but they aren't the right fit for every driver. Here's how diesel and gas compare on cost, performance, maintenance, and winter driving in PA and NJ, so you can decide which belongs in your driveway.
Diesel vs. gas at a glance
| Factor | Diesel | Gas |
|---|---|---|
| Fuel economy | Usually noticeably better, especially on the highway | Lower, especially when towing |
| Torque and towing | Strong low-end torque; excellent for heavy towing | Good, but works harder under heavy loads |
| Price of fuel | Usually costs more per gallon than regular | Usually cheaper per gallon |
| Upfront cost | Diesel engine options usually cost more | Lower |
| Emissions equipment | DEF fluid and a particulate filter on modern diesels | Simpler |
| Best driving style | Long highway trips and towing | Short trips and city or mixed driving |
| Used selection | Mostly pickups and full-size SUVs | Every type of vehicle |
Why diesel engines get better mileage and more torque
Diesel fuel holds more energy per gallon than gasoline, and diesel engines burn it more efficiently. The result is better miles per gallon and lots of torque at low engine speeds, which is exactly what you want when you're pulling a heavy trailer up a hill or merging onto the Turnpike with a load behind you.
The real costs of owning a diesel
- Fuel price: diesel usually costs more per gallon than regular gas, which cancels out part of the mileage advantage. The savings are biggest for drivers who log a lot of highway miles.
- Diesel exhaust fluid (DEF): most modern diesels use DEF to reduce emissions. You top it off every few thousand miles at a modest cost, and the vehicle can limit power if it runs out.
- Diesel particulate filter (DPF): the DPF traps soot and burns it off during highway driving. Lots of short trips can clog it, which can mean an expensive repair.
- Maintenance: diesels need fuel filters and specific oil, and some repairs cost more. Many owners find diesel engines very durable when properly maintained.
- Resale value: diesel trucks often hold their value well, which helps offset the higher purchase price.
Diesel in PA and NJ winters
Diesel fuel can thicken, or "gel," in very cold temperatures. Fuel stations in our area sell winterized diesel during cold months, and many diesel trucks have block heaters for frigid mornings. Diesels can also take longer to warm up, so if most of your driving is short winter trips around town, a gas engine is usually the easier choice.
Who should buy a diesel?
- You tow a camper, boat, horse trailer, or equipment regularly
- You drive a lot of highway miles each year
- You plan to keep the vehicle for a long time
- Most of your trips are long enough to fully warm the engine
Who should buy gas?
- Most of your driving is short trips, errands, or city traffic
- You tow rarely or only light loads
- You want the lowest purchase price and simplest maintenance
- You want the widest choice of used vehicles
What diesels can you find used?
Diesel options in smaller cars and SUVs have mostly disappeared, so most used diesels are trucks and big SUVs. Examples include the Chevy Silverado 1500, Chevy Tahoe and GMC Yukon with the 3.0L Duramax, the Ford F-150 Power Stroke (2018 to 2021), and heavy-duty pickups like the Ram 2500, Ford F-250, and Chevy Silverado 2500. See our guides to the Chevy Silverado 1500, Ford F-150, and GMC Yukon vs. Chevy Tahoe.
What to check on a used diesel
- Service records: regular oil and fuel filter changes matter more on a diesel.
- Emissions system: check for warning lights tied to the DPF or DEF system, and ask about any repairs.
- Towing history: heavy towing is normal for diesels, but check the hitch, brakes, and transmission fluid.
- Modifications: avoid trucks with removed or altered emissions equipment. They can fail inspection and be illegal to register.
- Cold start: the engine should start and idle smoothly without excessive smoke.
- Open recalls: run the VIN on NHTSA's recall lookup.
Diesel vs. hybrid vs. electric
If fuel savings are your main goal and you don't tow, a hybrid or electric vehicle may save you more than a diesel. Compare the options in hybrid vs. gas and electric vs. gas. Still deciding on a body style? Read truck vs. SUV.
Shop trucks and SUVs at CarVision
We get a lot of customers who want a diesel truck but barely tow. Our honest advice: if you're pulling a camper or boat regularly or putting serious highway miles on, a diesel is worth it. If most of your driving is short trips around town, the gas V8 or a turbo engine will cost less and give you fewer headaches.
Find the right truck or SUV
Compare diesel and gas trucks and SUVs at either CarVision showroom and talk through which engine fits how you drive.
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Frequently asked questions
Is diesel or gas better for a used car?
Gas is better for most drivers because it costs less up front, suits short trips and city driving, and has simpler emissions equipment. Diesel is better if you tow heavy loads or drive many highway miles.
Do diesel engines get better gas mileage?
Usually, yes. Diesel fuel holds more energy per gallon and diesel engines burn it efficiently, so diesels typically get better fuel economy, especially on the highway and when towing.
Is diesel more expensive to maintain?
Modern diesels need diesel exhaust fluid, fuel filter changes, and a healthy particulate filter, and some repairs cost more. Many diesels are very durable when properly maintained.
Are diesels bad for short trips?
Lots of short trips can be hard on a modern diesel because the particulate filter needs highway driving to burn off soot. Drivers who mostly make short trips are usually better off with gas.
Do diesel trucks work in PA and NJ winters?
Yes. Stations sell winterized diesel in cold months, and many diesel trucks have block heaters for very cold mornings.
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