Vehicle inspection questions on the CDL knowledge test

A knowledge question, not just a skills one

Inspection is part of the skills test, but it is also one of the federal knowledge areas for the General Knowledge test. Expect written questions on what to check, when, and what a defect means for whether you can drive.

Three times to inspect

Before the trip, during it at stops, and after it, when the driver reports what was found. Questions often give a situation, such as a stop for fuel, and ask what the driver should check then.

What the questions focus on

• Tires and wheels. Tread depth, cuts and bulges, mismatched tires, and loose or missing lug nuts.
• Brakes and steering. Too much free play in the steering wheel, and brake parts that are worn, loose or out of adjustment.
• Lights and reflectors. Working, clean and the right color.
• Cargo securement. Whether the load is tied down and stays that way, checked again soon after starting out.
• Emergency equipment. The fire extinguisher and warning devices for a stopped vehicle.

The answer the test looks for

When a question asks what to do about a safety defect, the right answer is almost never to drive on carefully. It is to have it repaired before driving, or to report it so it is fixed. Options that let the trip continue with a known safety problem are written to be wrong.

How to study it

Learn inspection as an order, from the front of the vehicle around to the back, so you can place any part in the sequence. Most questions on this topic become easy once you can say where in the check a part comes and what a fault there looks like.