FREE CO CDL Combination Test (2024)

1. Dollies with ABS are required to have a malfunction lamp:

2. When transporting cargo, the cargo should be checked:

only after the trip.
before the trip and after the first 150 miles.
before the trip and after the first 50 miles.
only before the trip.

3. Empty trucks:

require the same stopping distance than full trucks.
require a shorter stopping distance than full trucks.
require a greater stopping distance than full trucks.
None of the above.

4. Tests have shown that trucks with a high center of gravity are more likely to tip over, therefore you should:

put the lightest parts of the cargo under the heaviest parts.
distribute the cargo so the majority of the weight is on the steering axle.
distribute the cargo as low as possible.
All of the above.

5. When coupling, you should:

make sure the sliding fifth-wheel is locked.
make sure the trailer wheels are not chocked.
be aware that wrong coupling and uncoupling can be very dangerous.
make sure the trailer kingpin is bent.

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

7. If the spring brakes do not release when you push the trailer air supply control, you should:

check the electrical cables.
rev or lug the engine.
check the air line connections.
pump the brakes.

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

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

9. 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.
watch out for vehicles coming toward you and back up for them.
swing wide to the left before starting the turn.

10. Blocking and bracing are:

driving techniques used to regain control when your drive wheels start to skid.
used to keep cargo from sliding and to prevent movement of cargo.
coupling devices used to connect the service air lines from the truck or tractor to the trailer.
None of the above.

CO CDL COMBINATION PRACTICE TEST