- Which part of the kingpin should the locking jaws close around?
= THE SHANK
- There are several types of vehicle skids, and they require somewhat different actions to respond to them, however there is one rule that is important for all skids?
= RESTORE TRACTION TO TIRES
- If you cannot complete a turn without entering another traffic lane, you should turn wide as you?
= COMPLETE THE TURN (after the intersection)
- Your emergency air line breaks or gets pulled apart while you are driving, the loss of pressure will cause the?
=Trailer Emergency/Spring Brakes to come on.
- When driving a ABS equipped tractor trailer combination you should?
= Brake normally.
- You have a major leak in the service line and you put on the brakes, service air pressure will escape and cause the?
= Trailer Emergency/Spring brakes to come on.
- If the service line disconnects while you are driving, what will happen right away?
Nothing likely to happen UNTIL you apply the brake pedal
- After you supply air to the trailer, make sure the airlines are not crossed and the trailer brakes are working, this is done by?
- Applying then Releasing the Trailer Brakes
- Listening for brake action sounds.
- How do you supply air to the air tank on the trailer, air is supplied by?
= Setting/Push-in the Trailer Air Supply/Parking Valve. (RED)
- The safety catch for the fifth wheel locking lever must be ________ for a coupling to be complete?
= Over the Locking Lever
T/F?
A tractor bob-tailing (no trailer attached) takes longer to stop than a loaded combination vehicle.
TRUE
T/F?
- Hand valve/Trolley Valve/Johnson Bar should only be used for testing the trailer’s service brakes.
- You should not try to use the hand valve during normal driving to try and prevent a jackknife.
- Never use the hand valve as a parking brake.
TRUE
(COMBINATION TEST #2)
A device that allows the service brakes to be applied more quickly is?
= the Relay Valve.
When coupling a tractor and trailer, and you have connected the airlines, before backing underneath the trailer, what should you do?
- Supply air to the Trailer Brake system (push red valve)
- WaitUntil the whole air system is at normal pressure = 100 - 125 PSI.
- Then set the Trailer Brakes. (pull-out red valve)
- Proceed to Couple
After you have coupled the tractor to the trailer, you should always do which of the following?
- Check Trailer Brakes by doing a Tug Test.
- Make sure the jaws have locked around the Kingpin
Another name for the trailer hand valve is?
= JOHNSON BAR, TROLLEY VALVE.
The tractor protection valve is an in-cab valve that?
= Keeps air supplied to the Tractor brakes.
should the trailer break away, or start to leak
You are bob tailing and have a major air leak in the service brake air-line and you apply the brakes, service air pressure will escape and cause the?
= The Tractor Emergency/Spring Brakes to come on when the pressure drops below 45 PSI.
What are the 3 parts of the trailer kingpin?
the head
the shank
the base
Many Trailers made before 1975 do not have?
spring brakes
Trailers/Converter Dollies made after March 1st 1998 are required to have?
ABS
If you cross the air-lines on an old trailer without spring brakes, you could pull the trailer but will not have?
trailer brakes
