DOT Annual Inspection Checklist for Commercial Trucks

Every commercial vehicle needs a federal annual inspection under 49 CFR 396.17, and a missed or failed one can put your truck out of service. The good news: almost everything inspectors look at is something you can check yourself first.

What the inspection covers

The annual is a head-to-toe of the safety-critical systems. The big categories:

• Brakes — lining/pad thickness, drums/rotors, air-system function, slack adjuster travel, low-air warning.
• Steering — play in the box and linkage, kingpins, tie-rod ends.
• Suspension — springs, U-bolts, hangers, airbags, shocks.
• Tires and wheels — tread depth (4/32” steer, 2/32” others), sidewall condition, no cuts to cord, lug condition.
• Lighting — every required lamp and reflector working.
• Coupling — fifth wheel, kingpin, safety devices.
• Frame, fuel system, exhaust, cab, glass, wipers, horn, and emergency equipment.

The items that fail trucks most

In roadside data year after year, the repeat offenders are brakes out of adjustment, lighting/lamp violations, and tires. None of those should ever surprise you — they’re visible on a walk-around.

Prep so you pass the first time

Before the truck goes in, do your own pass: walk every lamp with the four-ways on, thump the tires and check tread and pressure, look for air leaks (charge the system, shut down, watch the gauge for pressure drop), check brake-adjustment indicators, and look underneath for fresh leaks, cracked springs, or loose U-bolts. Clean the truck — inspectors find more on a dirty truck because fresh leaks stand out against grime.

Tie it to your C service

The smart move is to schedule the annual alongside your major (C) preventive-maintenance service, so the truck is already opened up and on the lift. You fix what the inspection finds in the same visit instead of making a second trip.

Keep the inspection certificate and a copy in the cab — you’re required to. If you run more than a couple of trucks and tracking annuals across the fleet is getting away from you, that’s exactly the kind of thing a managed PM program keeps on the rails. Our shop can handle inspections and the repairs that come out of them.