CDL - Combination Vehicle
Practice Test ( 39 questions
and answers )
A tractor with a(n) ________ trailer requires the shortest amount of
stopping distance .
1. empty
2. fully loaded
3. lightly loaded
fully loaded
We have an expert-written solution to this problem!
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
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
you could lose your brakes while driving
Which part of the kingpin should the locking jaws close around?
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
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
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
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
the tractor protection valve to close
When you drive a set of doubles, which shut-off valve must be
closed in the last trailer?
1. Middle section
2. front section
3. back section
back section
Practice Test ( 39 questions
and answers )
A tractor with a(n) ________ trailer requires the shortest amount of
stopping distance .
1. empty
2. fully loaded
3. lightly loaded
fully loaded
We have an expert-written solution to this problem!
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
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
you could lose your brakes while driving
Which part of the kingpin should the locking jaws close around?
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
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
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
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
the tractor protection valve to close
When you drive a set of doubles, which shut-off valve must be
closed in the last trailer?
1. Middle section
2. front section
3. back section
back section
