CDL Pre-Trip Inspection Checklist

Correct answer: Safety — for yourself and for other road users

Safety is the most important reason you inspect your vehicle — safety for yourself and for everyone else on the road. A vehicle defect found during inspection can prevent a crash or breakdown.

Correct answer: To find problems that could cause a crash or breakdown before you drive

A pre-trip inspection helps you find problems that could cause a crash or breakdown. On the CDL skills test you must show you know whether the vehicle is safe to drive.

Correct answer: 4/32 inch

Front tires must have at least 4/32 inch of tread depth in every major groove. Bad wear on the front tires is especially dangerous because it makes the vehicle harder to steer and stop.

Correct answer: 2/32 inch

Tires other than the front (steer) tires need at least 2/32 inch of tread depth. The front tires require more — 4/32 inch — because of their steering and braking role.

Correct answer: Radial and bias-ply tires used together, or mismatched tire sizes

Do not mix radial and bias-ply tires, and do not run mismatched sizes. Also watch for cut or cracked valve stems and dual tires that touch each other or the vehicle.

Correct answer: The nuts may be loose

Rust around wheel nuts may mean the nuts are loose — check their tightness. After a tire is changed, stop a short while later and re-check the tightness of the nuts.

Correct answer: The front wheels

Regrooved, recapped, or retreaded tires are prohibited on the front wheels of a bus. Damaged rims and welded-repair wheels are also unsafe and should never be used.

Correct answer: More than 10 degrees (about 2 inches of movement on a 20-inch wheel)

Steering wheel play of more than 10 degrees — roughly 2 inches of movement at the rim of a 20-inch wheel — can make the vehicle hard to steer and should be repaired.

Correct answer: One-fourth or more of the leaves

If one-fourth or more of the leaves in a leaf spring are missing or broken, the vehicle is out of service — but any broken suspension part can be extremely dangerous because the suspension holds up the vehicle and its load.

Correct answer: Cracked drums, or shoes with oil, grease, or brake fluid on them

Look for cracked drums and for shoes or pads that are contaminated with oil, grease, or brake fluid, or that are worn dangerously thin, missing, or broken.

Correct answer: It can let poison fumes into the cab or sleeper berth

A broken exhaust system can leak poisonous fumes into the cab or sleeper berth. Check for loose, broken, or missing pipes, mufflers, and mounting brackets, and for parts leaking or rubbing.

Correct answer: A fire extinguisher, spare electrical fuses (unless it has circuit breakers), and warning devices for parked vehicles

Required emergency equipment includes a properly charged and rated fire extinguisher, spare electrical fuses (unless the vehicle has circuit breakers), and warning devices such as reflective triangles, fusees, or flares.

Correct answer: Three

You should carry three red reflective warning triangles (the alternatives are 6 fusees or 3 liquid-burning flares) to warn other drivers when your vehicle is stopped.

Correct answer: That the truck is not overloaded and the cargo is balanced and secured

Before each trip make sure the truck is not overloaded and that the cargo is balanced and secured. If the cargo is hazardous materials, also inspect for proper papers and placarding.

Correct answer: So you learn all the steps and are less likely to forget something

Doing the inspection the same way each time builds a routine, so you learn all the steps and are less likely to forget any part of it.