CDL Combination Test (2024) - FREE Vermont Practice Test

1. When the tractor protection valve closes, the trailer _______ brakes will come on.

2. When you park trailers without spring brakes, you should use wheel chocks:

to prevent air from escaping.
to prevent the transmission from shifting up.
to keep the trailer from moving.

3. When you use your mirrors while driving on the road, you should:

only use the driver's side mirror.
avoid checking them regularly.
check them quickly.

4. When approaching a vehicle with a distracted driver, you should:

change lanes quickly.
quickly pass the vehicle.
maintain your safe following distance.

5. The emergency air line:

supplies air to the trailer air tanks.
controls the emergency brakes on combination vehicles.
All of the above.

6. If there is a cargo fire in a van or box trailer, you should:

enlist the help of bystanders.
open the doors, especially if your cargo contains hazardous materials.
keep the doors shut.

7. Dual tires:

should always come in contact with each other.
should come in contact with each other whenever possible.
should not come in contact with each other.

8. The tractor protection valve:

supplies air to the trailer air tanks.
controls the emergency brakes on combination vehicles.
keeps air in the tractor brake system should the trailer break away or develop a bad leak.

9. If your trailer starts to skid, you should:

release the brakes to get traction back.
use the trailer hand brake (if you have one) to straighten out the rig.
keep the rear of your vehicle close to the curb.

10. When backing a trailer, if you turn the wheel left:

the cab will go right and the trailer will go left.
the cab will go left and the trailer will go right.
the cab and the trailer will go left.

COMBINATION PRACTICE TEST - VT CDL