FREE Texas Combination Practice Test (2023)

1. If you smell exhaust fumes in the cab, you should:

wait for the next stop, then inspect your vehicle.
open the windows.
stop immediately.
remember to conduct a post-trip inspection.

2. Which of the following is NOT part of the procedure to stop a trailer skid?

Releasing the brakes
Using the trailer hand brake to get traction back
Not using the hand brake
Recognizing the skid

3. In a vehicle with a dual air brake system:

one system supplies air to the trailer.
both systems typically operate the regular brakes on the rear axle.
each system has its own air tanks.
All of the above.

4. When backing, as soon as you see the trailer getting off the proper path, you should:

turn the top of the steering wheel in the opposite direction of the drift.
to keep a firm grip on the steering wheel and continue backing.
turn the top of the steering wheel in the direction of the drift.
None of the above.

5. Where are shut-off valves?

At the front of each trailer.
On converter dollies.
At the front and back of each trailer.
At the back of each trailer.

6. The best way to recognize that your trailer has started to skid is:

by using retarders.
by hearing squeaking noises from the wheels.
by seeing it in your mirrors.
None of the above.

7. The use of brakes on a steep downgrade is:

the main braking factor.
much more effective than the engine braking effect.
a supplement to the braking effect of the engine.
dangerous, and should be avoided at all costs.

8. You should use chocks when parking a trailer without spring brakes because:

it is required by law.
the brakes will hold only as long as there is air pressure in the trailer air tank.
it helps prevent brake failure.
it helps prevent skids.

9. When using a fire extinguisher, you should stay:

at whatever distance you think is safe.
as far away from the fire as possible.
at least 10 feet away from the fire.
as close to the fire as possible, without getting burnt.

10. Do not use the trailer hand valve in driving because:

the brakes can overheat and lose their braking power.
the trailer emergency brakes will come on.
of the danger of making the trailer skid.
All of the above.

CDL COMBINATION PRACTICE TEST TEXAS