DOT Inspector Vehicle Inspection Procedures 2

Question 1

During a DOT Level I inspection, what is the minimum brake lining thickness allowed before a brake is considered out-of-service on a steering axle?

Accepted Answer

1/8 inch

Answer

Steering axle brake lining must be at least 4mm (5/32 inch); however, the out-of-service criterion specifies no lining thickness less than 1/4 inch is permitted on steering axles.

Question 2

When inspecting air brake systems, what is the maximum allowable single-vehicle air loss rate at 90 PSI with the engine off and brakes released?

Accepted Answer

3 PSI per minute

Answer

FMCSA regulations allow no more than 3 PSI per minute air loss for single vehicles with brakes released.

Question 3

An inspector finds a cracked wheel in the disc area between the hand holes. What is the correct action?

Accepted Answer

Place the vehicle out of service immediately

Answer

Any crack in the disc area or bolt circle of a wheel is an out-of-service condition requiring immediate removal from service.

Question 4

Which of the following conditions would NOT place a vehicle out of service for steering defects?

Accepted Answer

A steering gear box that is securely mounted but shows minor surface rust

Answer

Surface rust on a securely mounted steering gear box is not an out-of-service condition, unlike broken parts, excessive play, or worn tie rod ends.

Question 5

Under FMCSA regulations, what is the maximum allowable slack adjuster travel for a Type 30 air brake chamber with a 6.5-inch stroke?

Accepted Answer

2.0 inches

Answer

A Type 30 brake chamber with a 6.5-inch stroke has a maximum allowable pushrod travel of 2.0 inches before being considered out of service.

DOT Inspector Certification Practice Test

DOT Inspector Certification Practice Test

DOT Inspector Vehicle Inspection Procedures 2