Buying a used diesel truck is a serious investment. Whether you’re looking at the Duramax or Power Stroke models we currently have on the lot, you want to ensure you’re getting a machine that’s ready to work. Here are five critical things to inspect before you sign the dotted line.
1. Check the Service History
Diesel engines can last a lifetime, but only if they’ve been maintained. Look for consistent oil changes and fuel filter replacements. A well-documented history is the best indicator of future reliability.
2. Inspect for “Blow-by”
With the engine running, safely remove the oil fill cap and set it upside down over the hole. If it’s blown off by pressure, that’s a sign of worn piston rings or cylinders—a costly repair you want to avoid.
3. Look at the Cold Start
Always ask to see the truck start when the engine is completely cold. Hard starting, excessive smoke, or rough idling can point to injector issues or glow plug problems.
4. Analyze the Exhaust
Blue smoke often means burning oil, while white smoke can indicate unburnt fuel or coolant leaks. A healthy diesel should have minimal smoke once it’s warmed up.
5. Test the Transmission
Diesel trucks produce massive torque. During your test drive, ensure the shifts are crisp and there’s no slipping, especially under acceleration. If you’re eyeing one of our heavy-duty trucks, we’ve already put them through these paces to ensure they’re road-ready!
