You're about to spend real money on a used truck, and the seller swears it runs great. The question that keeps you up: what's hiding under that shine? A good pre-purchase inspection is the cheapest insurance you'll ever buy.

Here's the checklist to work through before you hand over a dollar.

Start with the records, not the truck

Paperwork tells you more than a test drive. Ask for maintenance history, ECM (engine control module) reports, and any overhaul receipts.

  • ECM download — shows real idle time, hard braking events, average MPG, and true mileage. Odometers lie; the ECM usually doesn't.
  • Service records — consistent oil changes and DOT inspections mean an owner who cared.
  • Overhaul/rebuild receipts — a documented in-frame or overhaul can be a plus, but only with proof.
  • Accident and title history — check for a salvage or rebuilt title.

No records? Treat every system below as suspect and price accordingly.

Engine and drivetrain

Cold-start the truck yourself. A truck that's already warm when you arrive may be hiding hard-start or blow-by issues.

  • Watch the exhaust on startup — heavy blue or white smoke is a red flag.
  • Pull the oil cap and check for excessive blow-by (smoke pushing out).
  • Look under the truck for oil, coolant, and fuel leaks.
  • Check coolant for oil contamination and the oil for coolant (milky film).
  • On the drive: listen for turbo whine, feel for clutch slip, and run through every gear.

Frame, suspension, and aftertreatment

Frame and emissions problems are the ones that quietly drain your bank account.

  • Frame rails — look for cracks, welds, rust-through, and signs of past collision repair. A bent or repaired frame is a walk-away.
  • Suspension — check air bags for leaks, bushings for wear, and the ride height.
  • Aftertreatment (DPF/DEF/EGR) — ask about regen frequency and any check-engine or derate history. A clogged DPF or failing SCR system can cost thousands. Scan for stored fault codes.

Brakes and tires

These are your safety and your first inspection failures out on the road.

  • Measure brake shoe/pad thickness and check drums or rotors for cracks.
  • Inspect air lines for leaks; do a full air-brake test and time the pressure build-up.
  • Check tire tread depth, matching brands, and DOT date codes — old tires are dry-rotted no matter the tread.
  • Look for uneven wear that points to alignment or suspension problems.

Pay a mechanic. Every time.

The single best money you'll spend is a few hundred dollars on an independent heavy-duty mechanic doing a pre-purchase inspection. They'll catch what you can't and give you leverage to negotiate — or a reason to walk.

Spending $300 to avoid a $15,000 engine surprise is not a cost. It's the smartest trade you'll make all year. Our owner-operator resource center has more on protecting your equipment investment.

Make sure the truck qualifies before you buy

If your plan is to lease on and haul under an established carrier's authority, confirm the truck meets the standard first. ARI requires a sleeper semi that's a 2000 model or newer and DOT-ready. Buy something that won't pass, and you've bought a problem before your first load.

Get the inspection done, get the records, and buy with your eyes open. When your truck is ready to earn, you'll want freight that actually pays for it — running under ARI's authority gets you a dedicated dispatcher, an 82% revenue share, same-day pay, and zero escrow.

When your equipment is sorted, take a look at what leasing on with ARI looks like, or call (888) 600-9098 to talk it through.