CDL Combination Vehicle Practice Test Questions with Correct Answers 2026 | Complete Class A Study Guide

CDL-COMBINATIONVEHICLEPRACTICE b b b b




TEST QUESTIONS WITH CORRECT b b b b




ANSWERS2026//2027 b




A tractor with a(n)
b b b b trailer requires the shortest amount of stopping distance .
b b b b b b b b b




1. empty

2. fully loaded b




3. lightly loaded - CORRECT ANSWER-fully loaded
b b b b b




The air leakage rate for a combination vehicle ( engine off, brakes on) should not be more t
b b b b b b b b b b b b b b b b b




han
b psi per minute .
b b b b




1. 4 b




2. 6 b




3. 2 - CORRECT ANSWER-4
b b b b




If you do not do the final air brake check for air leaks and fix them before driving,
b b b b b b b b b b b b b b b b b




1. you could lose your brakes while driving
b b b b b b




2. your fuel usage will increase b b b b




3. tire pressure will drop - CORRECT ANSWER-you could lose your brakes while driving
b b b b b b b b b b b b




Which part of the kingpin should the locking jaws close around? - CORRECT ANSWER-
b b b b b b b b b b b b b




The shank
b b




Glad hands are used to connect the ....
b b b b b b b




1. kingpin from the trailer to the locking jaws of the fifth wheel
b b b b b b b b b b b




2. electrical lines from the tractor to the trailer b b b b b b b

, 3. service and emergency air lines from the truck or tractor to the trailer -
b b b b b b b b b b b b b




CORRECT ANSWER-service and emergency air lines from the truck or tractor to the trailer
b b b b b b b b b b b b b




Trucks roll over more easily when fully loaded and are
b b b b b b b b b




1. ten times more likely to roll over in a crash than empty rigs
b b b b b b b b b b b b




2. five times more likely to roll over in a crash than empty rigs
b b b b b b b b b b b b




3. two times more likely to roll over in a crash than empty rigs - CORRECT ANSWER-
b b b b b b b b b b b b b b b




ten times more likely to roll over in a crash than empty rigs
b b b b b b b b b b b b b




In general, the higher your trucks center of gravity, the ...
b b b b b b b b b b




1. easier it is to turn over b b b b b




2. more stable it is when turning b b b b b




3. easier it is to turn around corners - CORRECT ANSWER-easier it is to turn over
b b b b b b b b b b b b b b




You are driving a combination vehicle when the trailer breaks away, pulling apart both air li
b b b b b b b b b b b b b b b




nes. You would expect the trailer brakes to come on and ...
b b b b b b b b b b b b




1. the tractor to lose all air pressure
b b b b b b




2. the tractor protection valve to close
b b b b b




3. the trailer supply valve to stay open - CORRECT ANSWER-
b b b b b b b b b




the tractor protection valve to close
b b b b b b




When you drive a set of doubles, which shut-off valve must be closed in the last trailer?
b b b b b b b b b b b b b b b b




1. Middle section b




2. front section b




3. back section - CORRECT ANSWER-back section
b b b b b