Question 1

Why should a driver perform a post-trip inspection at the end of a route, not just a pre-trip inspection?

Accepted Answer

It helps catch any new issues from the trip before the vehicle is used again — A post-trip inspection helps identify any new issues that developed during the trip, so they can be addressed before the vehicle is used again.

Question 2

What is the main purpose of a pre-trip inspection, distinct from a post-trip inspection?

Accepted Answer

To catch existing problems before operating the vehicle, rather than after a trip is already done — A pre-trip inspection is meant to catch problems before they can cause a breakdown or crash, while a post-trip inspection catches new issues that developed during the trip.

Question 3

What is the purpose of a Driver Vehicle Inspection Report (DVIR)?

Accepted Answer

To document any defects found so they can be reported and repaired before the vehicle is driven again — A DVIR creates a documented record of any defects so a carrier can ensure they are repaired before the vehicle is dispatched again.

Question 4

What is the federal minimum tread depth for front steering axle tires on a commercial vehicle?

Accepted Answer

4/32 of an inch — Federal rules require at least 4/32 of an inch of tread on front steering axle tires, a stricter standard than the 2/32 inch minimum for other tire positions.

Question 5

What is the federal minimum tread depth for tires other than the front steering axle on a commercial vehicle?

Accepted Answer

2/32 of an inch — Non-steering tires have a federal minimum of 2/32 of an inch of tread, less strict than the 4/32 inch required on the front steering axle.

Question 6

Why check wheel fasteners (lug nuts) during a vehicle inspection?

Accepted Answer

Loose or missing fasteners can allow a wheel to come off while the vehicle is moving — Loose or missing wheel fasteners can lead to a wheel separating from the vehicle while driving, making this a critical safety check, not a cosmetic one.

Question 7

Why is it recommended to follow the same systematic sequence during every pre-trip inspection?

Accepted Answer

A consistent routine makes it less likely that a component gets overlooked — Following the same sequence every time builds a habit that reduces the chance of accidentally skipping a component during inspection.

Question 8

Why should a driver check under the vehicle for fluid leaks during an inspection?

Accepted Answer

A leak can signal a developing mechanical problem that could cause a breakdown or fire — A fluid leak often points to a developing mechanical issue, which is why checking underneath the vehicle is part of a thorough pre-trip inspection.

Question 9

What safety equipment is a commercial vehicle generally required to carry?

Accepted Answer

A properly rated and charged fire extinguisher — Federal rules require most commercial vehicles to carry a properly rated, charged fire extinguisher as standard safety equipment.

Vehicle Inspection Practice Questions