FREE OK CDL Combination Test - Practice Test 2024

1. Passive railroad crossings:

have at least one traffic control device.
should never be crossed using a CMV.
do not have traffic control devices.

2. The emergency air line does NOT:

supply air to the trailer air tanks.
control the emergency brakes on combination vehicles.
pump air into the relay valves, allowing the trailer brakes to be applied more quickly.

3. You are checking the tractor-trailer connection to make sure it is safe and secure. The landing gear should be:

raised slightly off the ground.
fully lowered.
fully raised.

4. On front tires, tread should be at least:

5. You are driving a combination vehicle and must use your brakes to avoid a crash. You should:

push the brake pedal as hard as you can and hold it there.
use stab braking or controlled braking.
brake lightly and hold the steering wheel firmly.

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

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

7. Which of the following is NOT part of a trailer air line system?

8. When the ______ closes, it stops any air from going out of the tractor.

9. You are driving a modern truck with a manual transmission. When going down a hill you should usually:

shift into neutral and coast.
use the same gear you would use to go up the hill.
use a lower gear than would be required to go up the hill.

10. If your vehicle is equipped with air brakes, loss of air pressure in the emergency line will cause:

the trailer emergency brakes to come on.
the vehicle to slide back and forth.
the springs to put on the brakes.

OKLAHOMA CDL COMBINATION PRACTICE TEST