Diesel vs gas
Everyone asks whether the diesel is worth it. The honest answer is that it depends almost entirely on how many miles you drive and what you pull — and for a lot of buyers, the gas truck is the better financial decision even though it feels like the lesser choice.
The purchase price gap
A diesel three-quarter ton typically carries a premium of several thousand dollars over the same truck with a gas V8, and that gap holds up on the used market longer than most people expect. It’s the first number in the equation and the one you can’t avoid.
What complicates it is that the premium isn’t fixed. It narrows on higher-mileage trucks and widens on well-maintained ones, because buyers who want diesels want them badly and are picky about history.
Fuel, and why the math surprises people
Diesels are genuinely more efficient, particularly under load. The catch is that diesel fuel usually costs more per gallon than regular, and DEF is an ongoing expense that gas trucks don’t have. The efficiency advantage is real but the price advantage runs the other way, so the two partly cancel.
Where the diesel pulls decisively ahead is towing. Unloaded, the gap narrows enough that a light-duty user may never recover the purchase premium.
A rough comparison
| Scenario | Gas V8 | Diesel |
|---|---|---|
| Empty highway | 15–17 mpg | 19–22 mpg |
| Loaded bed, no trailer | 13–15 mpg | 17–19 mpg |
| Towing 10,000 lb | 7–9 mpg | 11–13 mpg |
| City / stop-and-go | 12–14 mpg | 14–16 mpg |
Figures are typical ranges for late-model three-quarter tons, not manufacturer claims. Your right foot and Colorado’s grades will move them.
Maintenance is where it gets expensive
This is the part that catches people. Diesel maintenance costs more across the board — more oil per change, fuel filters on a schedule, and emissions components that are not cheap when they fail.
- Oil changes take significantly more oil and a bigger filter
- Two fuel filters on most modern diesels, replaced on a schedule
- DEF fluid as an ongoing consumable
- Emissions components that are expensive out of warranty
- Injectors and turbos: rare, but costly when they go
None of this is a reason to avoid a diesel. It’s a reason to budget honestly for one, and to care a great deal about the maintenance history of the specific truck you’re looking at.
Where the diesel wins outright
If you tow heavy regularly, there’s no argument. Exhaust brakes on long descents, more torque low in the rev range, and less strain on the drivetrain all matter on a mountain grade. In Colorado especially, anyone pulling a loaded gooseneck over a pass will feel the difference every single trip.
Resale is the other advantage. Diesels hold value better, which claws back part of the purchase premium when you sell.
So which should you buy?
Drive under about 15,000 miles a year and tow occasionally, and the gas truck likely costs you less overall. Drive more than that, or tow heavy most weeks, and the diesel starts making sense — and past a certain point it isn’t close.
If you’re on the fence, come drive both. We usually have each on the lot and half an hour behind the wheel settles it faster than any article will.
High miles or heavy towing, buy the diesel. Light use, buy the gas truck and put the difference toward something else. And whichever you choose, care more about the maintenance records than the badge on the fender.
Drive both
We usually have a gas and a diesel three-quarter ton on the lot. Half an hour settles the argument.
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