Is a Used Diesel Truck Worth It in South Dakota? Duramax vs. Power Stroke vs. Cummins

Duramax vs. Power Stroke vs. Cummins

Horsepower, torque and tow ratings change from one model year to the next and with each configuration, so compare the exact trucks you're looking at. For towing numbers, check the door-jamb sticker and the owner's manual, and we'll confirm the ratings for a specific VIN.

I don't pick a used diesel by the badge. I pick it by the records: regular oil changes, fuel filters done on schedule and no warning lights. A well-kept truck with any of the three engines beats a neglected one with either of the others.

Scott Kennedy, Service Manager

Half-ton 3.0L diesel or heavy-duty?

The 3.0L half-tons (Silverado or Sierra 1500 Duramax, Ram 1500 EcoDiesel, F-150 Power Stroke) are built for fuel economy and moderate towing in a truck that drives like a regular pickup. When MotorWeek tested the 2020 Silverado 3.0L, it reported 33 mpg highway, a pickup record at the time, and a 9,300-pound tow rating on the truck it drove.

A 2500 or 3500 is the tool for a big fifth-wheel camper, a loaded livestock or equipment trailer, or a heavy wheelhouse fish house. Heavy-duty trucks usually ride stiffer and cost more to buy and run, so they make the most sense when the trailer behind them is heavy and frequent.

Our towing guide walks through trailer weights and payload in plain words.

Cold starts at 20 below

Plug it in

A block heater warms the engine coolant so the engine turns over more easily and makes heat sooner. Your owner's manual lists the temperature at which the maker recommends using it. If a used truck doesn't have one, our service department installs block heaters. Before winter, look the cord over for cracks and corrosion; our winter checklist covers what to watch for.

Run winter-blend fuel

Diesel contains wax. When it gets cold enough, the wax forms crystals that can plug the fuel filter and cause hard starts. CHS puts the cloud point of No. 2 diesel at about 14 degrees F. No. 1 diesel has less wax, and blending it in lowers the cloud point, by about 3 degrees for every 10 percent of No. 1 added. Cenex says that when overnight lows get near 30 degrees, it's time for a winter blend. In the cold months, buy diesel from stations that sell a winter blend, and ask if the pump doesn't say.

Add anti-gel before a cold snap

Many owners add a winter anti-gel additive at fill-up ahead of a deep freeze. Use a product your owner's manual allows, and follow the label.

If a diesel won't start because the fuel has gelled, stop cranking it. Get it somewhere warm, or call us. Cranking a gelled truck mostly just runs the batteries down.

Scott Kennedy, Service Manager

DEF freezes, and that's normal

Diesel trucks with a DEF tank use the fluid to clean up their exhaust. DEF freezes at 12 degrees F. Mitchell 1, a repair-information publisher, says frozen DEF will not stop a normal start or normal driving, and most systems have a built-in tank heater that thaws the fluid as you drive. Check your owner's manual for your truck's specifics.

• Don't fill DEF jugs or the tank to the brim in winter. Frozen fluid expands, and a full container can crack.
• If a DEF warning stays on after the truck is fully warmed up and has been driven a while, have it checked. A failed tank heater or sensor is a repair, not a weather quirk.

Is a used diesel worth it for you?

Probably yes if

• You tow heavy and often: campers, livestock, equipment or a big fish house.
• You put on lots of highway miles, like regular runs from Sioux Falls to Pierre or Rapid City.
• You keep trucks a long time and keep up with the maintenance.

Probably not if

• Most trips are short and in town. A diesel particulate filter cleans itself by burning off soot, and it needs hot exhaust to do it. One automaker's service bulletin warns that prolonged short trips can clog the filter, and says cleaning works best at a steady speed above about 38 mph for 20 to 30 minutes.
• You want the cheapest truck to run. A diesel adds DEF, fuel filters and emissions parts to the maintenance list.
• You rarely tow more than a light trailer. A gas half-ton usually does that job for less money. The diesel was a pricey option when new; Ford charged $4,995 for it on popular F-150 configurations.

What to check on any used diesel

• Service records, especially oil and fuel filter changes.
• No check-engine, DEF or emissions warnings, and a clean scan.
• A working block heater and a cord in good shape.
• Hitch and wiring condition. Hard towing isn't bad by itself, but ask how the truck was used.
• Open recalls. Run the VIN at nhtsa.gov/recalls.
• Coverage. On trucks that qualify, our FMC Certified warranty lists the factory turbo, the injection pump and the injectors under engine coverage, for 3 months or 3,000 miles.

Buying a diesel somewhere else? Our service center does pre-purchase inspections. Call (605) 250-7474.