FREE SD CDL Combination Test - Practice Test 2024

1. Which of the following is NOT part of inspecting the coupling?

Checking for enough clearance between the rear of the tractor frame and the landing gear.
Making sure the fifth-wheel jaws have closed around the shank of the kingpin.
Making sure there is no space between the upper and the lower fifth-wheel
Checking that the locking lever is in the "lock" position

2. Which of the following is NOT a good rule for using turn signals?

Signal continuously until you have completed the turn.
Signal well before you turn.
Put your turn signal on after the turn.
Cancel your signal after you have turned.

3. For a cargo fire in a box trailer, you should:

wait 10 minutes before opening the doors.
keep the doors shut.
open the doors immediately and use the fire extinguisher.
use the fire extinguisher on the doors.

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

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

5. Which of these statements is true?

Large combination vehicles take longer to stop when they are fully loaded than when they are empty.
Trailer skids are more likely to happen when the trailer is empty or lightly loaded.
"Bobtail" tractors can take longer to stop than a combination vehicle loaded to maximum gross weight.
All of the above.

6. Poor weight balance:

can make vehicle handling more difficult.
increases fuel efficiency.
makes it easier to turn.
improves handling.

7. If you are driving a 30 foot vehicle at 35 mph, you should leave at least _______ between your vehicle and the vehicle in front of you.

8. When parking a trailer without spring brakes, it is very important for safety that you use wheel chocks. Why?

if you don't use wheel chocks, supply air will be sent to the service line instead of going to charge the trailer air tanks.
The air could leak out of the trailer air tank, releasing its emergency brakes.
You may not notice a major leak in the service line until you try to put the brakes on.
None of the above.

9. If your truck catches fire, the first thing you should do is to:

get the vehicle off the road and park near other vehicles.
pull off the road and park in an open area.
pull into a service station and call for help.
get off the vehicle, open the hood and start shooting foam to keep the engine cool.

10. After coupling the trailer, begin raising the landing gear by using:

SOUTH DAKOTA CDL COMBINATION PRACTICE TEST