FREE California Combination Practice Test (2023)

1. If the safety relief valve in the air brake system releases air:

something is wrong.
this will supply more power to the brakes.
the valve is fully operational.

2. When driving a 50 foot combination vehicle at 50 mph in ideal conditions, you should keep at least ____ seconds of space in front of you.

3. When you turn suddenly while pulling doubles, which trailer is most likely to turn over?

The rear trailer is twice as likely to turn over as the tractor.
All trailers are equally likely to turn over.
The front trailer is twice as likely to turn over as the tractor.

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.
turn the top of the steering wheel in the direction of the drift.
to keep a firm grip on the steering wheel and continue backing.

5. To test the service brake:

gently try to pull forward with the trailer parking brake on, then release the brake.
shift your transmission to a low gear, pump the brake pedal three times, then hold it down for five seconds.
push the brake pedal firmly while going about 5 mph.

6. If you cannot make a right turn without entering another traffic lane, you should:

turn wide as you complete the turn.
turn wide before you start the turn.
swing wide to the left before starting the turn.

7. Cargo tie-downs are used to:

prevent freezing.
prevent right-turn accidents.
keep cargo from shifting or falling.

8. When driving on slippery roads, you should NOT:

use the engine brake.
try to anticipate stops early.
go slowly.

9. If the drive wheels begin to spin when accelerating, you should:

continue to accelerate.
take your foot off the accelerator.
brake gently.

10. You are coupling a semi-trailer to your tractor but have not yet backed under. The trailer is at the right height when:

the locking jaws are around the head of the kingpin.
it will be raised slightly when the tractor is backed under it.
the end of the kingpin is even with the top of the fifth wheel.

CDL COMBINATION PRACTICE TEST CALIFORNIA