CDL COMBINATION VEHICLE PRACTICE TEST TEST BANK 2026 UPDATED QUESTIONS WITH ANSWERS GRADED A+

CDL COMBINATION VEHICLE PRACTICE
TEST TEST BANK 2026 UPDATED
QUESTIONS WITH ANSWERS GRADED A+

⩥ The air leakage rate for a combination vehicle ( engine off, brakes on)
should not be more than _____ psi per minute .
1. 4
2. 6
3. 2. Answer: 4


⩥ If you do not do the final air brake check for air leaks and fix them
before driving,
1. you could lose your brakes while driving
2. your fuel usage will increase
3. tire pressure will drop. Answer: you could lose your brakes while
driving


⩥ Which part of the kingpin should the locking jaws close around?.
Answer: The shank


⩥ Glad hands are used to connect the ....
1. kingpin from the trailer to the locking jaws of the fifth wheel
2. electrical lines from the tractor to the trailer

, 3. service and emergency air lines from the truck or tractor to the trailer.
Answer: service and emergency air lines from the truck or tractor to the
trailer


⩥ Trucks roll over more easily when fully loaded and are
1. ten times more likely to roll over in a crash than empty rigs
2. five times more likely to roll over in a crash than empty rigs
3. two times more likely to roll over in a crash than empty rigs. Answer:
ten times more likely to roll over in a crash than empty rigs


⩥ In general, the higher your trucks center of gravity, the ...
1. easier it is to turn over
2. more stable it is when turning
3. easier it is to turn around corners. Answer: easier it is to turn over


⩥ You are driving a combination vehicle when the trailer breaks away,
pulling apart both air lines. You would expect the trailer brakes to come
on and ...
1. the tractor to lose all air pressure
2. the tractor protection valve to close
3. the trailer supply valve to stay open. Answer: the tractor protection
valve to close