CDL Combination NEWEST 2025 – 2026
UPDATED QUESTIONS FROM ACTUAL
EXAM COMPLETE QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED
ANSWERS) |ALREADY GRADED
A+||BRAND NEW!!
For coupling to be completed, the safety catch for the fifth wheel locking lever
must be
a) Through the locking lever
b) Over the locking lever
c) Straight up
b) Over the locking lever
You are coupling a tractor to a semi-trailer. You have connected the air lines.
Before backing under the trailer, you should
a) Pull ahead to test the glad hands connections
b) Supply air to the trailer system and then pull out the air supply knob
c) Make sure that the trailer brakes are off
b) Supply air to the trailer system and then pull out the air supply knob
You should not back a tractor under a trailer until the whole air system is
a) At normal pressure
,b) Between 60 and 80 psi
c) Bled down to half the maximum pressure
a) At normal pressure
The service line
a) Carries air to the cab of the rig to cool it
b) Carries air to the parking brake to control the trailer brakes
c) Carries air to a relay valve that allows the trailer brakes to be applied quickly
c) Carries air to a relay valve that allows the trailer brakes to be applied quickly
When you check the lower fifth wheel, you do NOT need to check
a) That there are no missing parts
b) That you cannot see any space between the upper and lower fifth wheels
c) That the shut-off valves completely closed
d) Whether it has enough grease
c) That the shut-off valves completely closed
Which of the following is most likely to roll over?
a) The rear trailer of a triple
b) The middle trailer of a triple
c) The rear trailer of a double
d) The front trailer of a double
a) The rear trailer of a triple
What does the trailer air supply control do?
a) By pushing it in, you supply the tires with air
b) By pushing it in, you supply the trailer with air
, c) By pulling it out, you remove air from overinflated tires
d) By pulling it out, you supply the trailer with air
b) By pushing it in, you supply the trailer with air
When parking a vehicle that does not have spring brakes, you should use chocks
a) To keep the trailer from offtracking so much
b) To stop the trailer from jackknifing
c) To help the trailer go more quickly
d) To keep the trailer from moving
d) To keep the trailer from moving
Which of the following should you do if you want to back into a curved path on
the driver's side?
a) Drive slowly while you are backing
b) Use your mirrors on both sides
c) First, check your path carefully, by getting out and walking around the vehicle
d) Do all of the above
d) Do all of the above
Which of the following is NOT a purpose of the emergency air line?
a) To control a combination vehicle's emergency brakes
b) To supply air to the trailer's air tanks
c) To cause the trailer emergency brakes to be applied if the emergency air line
loses pressure
d) To supply air to relay valves that help the foot brake operate more quickly
d) To supply air to relay valves that help the foot brake operate more quickly
Which of the following is NOT true about an antilock braking system (ABS)?
a) You will find it on all tractors built after March 1998
UPDATED QUESTIONS FROM ACTUAL
EXAM COMPLETE QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED
ANSWERS) |ALREADY GRADED
A+||BRAND NEW!!
For coupling to be completed, the safety catch for the fifth wheel locking lever
must be
a) Through the locking lever
b) Over the locking lever
c) Straight up
b) Over the locking lever
You are coupling a tractor to a semi-trailer. You have connected the air lines.
Before backing under the trailer, you should
a) Pull ahead to test the glad hands connections
b) Supply air to the trailer system and then pull out the air supply knob
c) Make sure that the trailer brakes are off
b) Supply air to the trailer system and then pull out the air supply knob
You should not back a tractor under a trailer until the whole air system is
a) At normal pressure
,b) Between 60 and 80 psi
c) Bled down to half the maximum pressure
a) At normal pressure
The service line
a) Carries air to the cab of the rig to cool it
b) Carries air to the parking brake to control the trailer brakes
c) Carries air to a relay valve that allows the trailer brakes to be applied quickly
c) Carries air to a relay valve that allows the trailer brakes to be applied quickly
When you check the lower fifth wheel, you do NOT need to check
a) That there are no missing parts
b) That you cannot see any space between the upper and lower fifth wheels
c) That the shut-off valves completely closed
d) Whether it has enough grease
c) That the shut-off valves completely closed
Which of the following is most likely to roll over?
a) The rear trailer of a triple
b) The middle trailer of a triple
c) The rear trailer of a double
d) The front trailer of a double
a) The rear trailer of a triple
What does the trailer air supply control do?
a) By pushing it in, you supply the tires with air
b) By pushing it in, you supply the trailer with air
, c) By pulling it out, you remove air from overinflated tires
d) By pulling it out, you supply the trailer with air
b) By pushing it in, you supply the trailer with air
When parking a vehicle that does not have spring brakes, you should use chocks
a) To keep the trailer from offtracking so much
b) To stop the trailer from jackknifing
c) To help the trailer go more quickly
d) To keep the trailer from moving
d) To keep the trailer from moving
Which of the following should you do if you want to back into a curved path on
the driver's side?
a) Drive slowly while you are backing
b) Use your mirrors on both sides
c) First, check your path carefully, by getting out and walking around the vehicle
d) Do all of the above
d) Do all of the above
Which of the following is NOT a purpose of the emergency air line?
a) To control a combination vehicle's emergency brakes
b) To supply air to the trailer's air tanks
c) To cause the trailer emergency brakes to be applied if the emergency air line
loses pressure
d) To supply air to relay valves that help the foot brake operate more quickly
d) To supply air to relay valves that help the foot brake operate more quickly
Which of the following is NOT true about an antilock braking system (ABS)?
a) You will find it on all tractors built after March 1998
