Combination Test - Texas CDL Complete Exam
Preparation for Commercial Driver’s License
In coupling, just before the tractor is coupled with the trailer you should:
~CORRECT ANSWER~✓✓connect the emergency and service air lines.
In coupling, you should not move the tractor after it is coupled until you
push in the air supply knob and: ~CORRECT ANSWER~✓✓wait until the
air pressure is normal.
What happens immediately if the service air line comes apart while
driving, but the emergency line is okay? ~CORRECT
ANSWER~✓✓Nothing is likely to happen until you press the brakes.
In coupling, before you back under the trailer, how do you lock the trailer
brakes? ~CORRECT ANSWER~✓✓Pull out the yellow air supply knob.
For the coupling to be complete, the safety catch for the fifth wheel locking
lever must be: ~CORRECT ANSWER~✓✓over the locking gear.
What is the air leakage rate for a combination vehicle with the engine and
brakes off? ~CORRECT ANSWER~✓✓Less than 3 PSI per minute.
, What is the maximum air leakage rate for a combination vehicle with the
engine off and the brakes on? ~CORRECT ANSWER~✓✓4 PSI per minute.
A driver crosses the air lines when hooking up to an old trailer. What will
happen? ~CORRECT ANSWER~✓✓If the trailer has no spring brakes, he or
she could drive away but wouldn't have trailer brakes.
To unlock the fifth wheel, pull the release handle to the: ~CORRECT
ANSWER~✓✓open position.
When driving a set of doubles, it is necessary to close the: ~CORRECT
ANSWER~✓✓back shut-off valve in the last trailer.
You are coupling a semitrailer to your tractor but have not yet backed
under. The trailer is at the right height when: ~CORRECT ANSWER~✓✓it
will be raised slightly when the tractor is backed under it.
Air and electric lines from the tractor to the trailer should be: ~CORRECT
ANSWER~✓✓secured, but with enough slack for turns.
When uncoupling a trailer, after you have shut off the trailer air supply
and locked the trailer brakes, you should: ~CORRECT ANSWER~✓✓back
up gently to ease pressure on the fifth wheel locking jaws.
Preparation for Commercial Driver’s License
In coupling, just before the tractor is coupled with the trailer you should:
~CORRECT ANSWER~✓✓connect the emergency and service air lines.
In coupling, you should not move the tractor after it is coupled until you
push in the air supply knob and: ~CORRECT ANSWER~✓✓wait until the
air pressure is normal.
What happens immediately if the service air line comes apart while
driving, but the emergency line is okay? ~CORRECT
ANSWER~✓✓Nothing is likely to happen until you press the brakes.
In coupling, before you back under the trailer, how do you lock the trailer
brakes? ~CORRECT ANSWER~✓✓Pull out the yellow air supply knob.
For the coupling to be complete, the safety catch for the fifth wheel locking
lever must be: ~CORRECT ANSWER~✓✓over the locking gear.
What is the air leakage rate for a combination vehicle with the engine and
brakes off? ~CORRECT ANSWER~✓✓Less than 3 PSI per minute.
, What is the maximum air leakage rate for a combination vehicle with the
engine off and the brakes on? ~CORRECT ANSWER~✓✓4 PSI per minute.
A driver crosses the air lines when hooking up to an old trailer. What will
happen? ~CORRECT ANSWER~✓✓If the trailer has no spring brakes, he or
she could drive away but wouldn't have trailer brakes.
To unlock the fifth wheel, pull the release handle to the: ~CORRECT
ANSWER~✓✓open position.
When driving a set of doubles, it is necessary to close the: ~CORRECT
ANSWER~✓✓back shut-off valve in the last trailer.
You are coupling a semitrailer to your tractor but have not yet backed
under. The trailer is at the right height when: ~CORRECT ANSWER~✓✓it
will be raised slightly when the tractor is backed under it.
Air and electric lines from the tractor to the trailer should be: ~CORRECT
ANSWER~✓✓secured, but with enough slack for turns.
When uncoupling a trailer, after you have shut off the trailer air supply
and locked the trailer brakes, you should: ~CORRECT ANSWER~✓✓back
up gently to ease pressure on the fifth wheel locking jaws.
