Combination Test 1

1. You should not back a tractor under a trailer until the whole air system is:
Between 60 and 80 psi
At normal pressure
Bled down to half the maximum pressure

2. You are coupling a semi trailer to your tractor but have not yet backed under. The trailer is at the right height when:
It will be raised slightly when the tractor is backed under it.
The kingpin is about 1 1/4 inches above the fifth wheel.
The end of the kingpin is even with the top of the fifth wheel.

3. Which part of the kingpin should the locking jaws close around?
The base
The shank
The head

4. When you get ready to back under the semi trailer you should line up:
About 12 degrees off the line of the trailer.
The kingpin to engage the driver's side locking jaw first.
Directly in front of the trailer.

5. How should you test the tractor semi trailer connection for security?
Pull gently forward in low gear against the locked trailer brakes, then look at it carefully.
Put the tractor in gear and pull ahead with a sharp jerk.
Rock the trailer back and forth with the trailer brakes locked.

6. When should you use the hand valve to park a combination vehicle?
To park at loading docks
To park on a grade

7. You supply air to the trailer tanks by:
Pushing in the trailer air supply valve.
Pulling out the trailer air supply valve.
Connecting the service line glad hand.

8. Why should you be sure that the fifth wheel plate is greased as required?
To reduce heat and noise
To prevent steering problems
To ensure good electrical connections

9. After you supply air to the trailer, make sure the air lines are not crossed and The trailer brakes are working. This is done by:
Applying and releasing the trailer brakes and listening for brake sounds.
Lifting the brake pedal.
Turning on the parking brakes from the cab.

10. There are two things that a driver can do to prevent a roll over. They are: (1) Keep the cargo as close to the ground as possible; and (2):
Make sure that the brakes are properly adjusted.
Keep the fifth wheel's free play as tight as possible.
Go slowly around turns.