CDL Combination Vehicles Endorsement/Topics/Inspecting
Inspecting covers 15 questions in the QuizCram bank (15% of all questions), ranking as the fourth biggest domain for the CDL combination vehicles endorsement exam. Questions are written against the official Original practice questions on the combination vehicles endorsement, written from the federal knowledge requirements in 49 CFR Part 383 and the public CDL manual facts. The real test is a multiple-choice knowledge test, and you need 80% to pass. Try the 3 free sample questions below to test your understanding of these core rules.
15 questions, the fourth biggest topic. The ring is its size next to the biggest.
Inspecting1 of 3
The answer
Answer: C. The jaws must hold the shank of the kingpin. If they are on the head, the trailer could come loose. Jaws on the head, around the base plate or open beside the pin would not hold the trailer, because only a grip on the shank keeps the kingpin locked in.
Source: 6.5.1 - Additional Things to Check during a Walk-around Inspection
Inspecting2 of 3
The answer
Answer: C. There are more things to inspect on a combination vehicle than on a single vehicle. There are also some new things to check. A three-step check, an inspection without the air brake checks or a weekly mechanic's check would miss defects, since the driver does the seven-step inspection with extra items for the coupling system.
Source: 6.5 - Inspecting a Combination Vehicle
Inspecting3 of 3
The answer
Answer: B. The hand valve is used to test the trailer brakes. In normal operation the foot pedal controls them. Pressing the pedal with the engine off, pulling with the supply knob out or disconnecting the trailer would not show that the hand valve applies the trailer service brakes.
Source: 6.5.2 - Combination Vehicle Brake Check
QuizCram covers 15 practice questions in the Inspecting domain, mapped directly to the official examination blueprint.
The benchmark score is 80% (Multiple-choice knowledge test · 80% to pass (49 CFR 383.135) · item count set by your state).
Yes. All questions on QuizCram are written against official handbooks and blueprint specifications with legal citations.