# When coupling the proper position of the fifth wheel is what?

## When coupling the proper position of the fifth wheel is what?

When coupling, the proper position of the fifth wheel is: Tilted Down towards the end of the tractor. A trailer is most likely to jackknife when it is: Empty.

How does a 5th wheel coupling work?

As the connected truck turns, the downward-facing surface of the semi-trailer (with the kingpin at the center) rotates against the upward-facing surface of the fixed fifth wheel, which does not rotate. To reduce friction, grease is applied to the surface of the fifth wheel.

### How much space should be allowed between upper and lower fifth wheel after coupling?

no space
There should be no space between the upper and lower fifth wheel.

How does a fifth wheel locking mechanism work?

The fifth wheel is equipped with a locking mechanism including a jaw slidably connected to the top plate and slidable between a closed position where the jaw blocks passage of a kingpin out of the throat of the fifth wheel and an open position where a kingpin may pass into and out of the throat of the fifth wheel.

#### When you get ready to back under the semi trailer you should line up?

4. When you get ready to back under the semi trailer you should line up: A About 12 degrees off the line of the trailer.

When hooking a tractor to a trailer you will know the trailer is at the correct height when the?

The trailer is at the right height when: It will be raised slightly when the tractor is backed under it. Which part of the kingpin should the locking jaws close around?

## What is the safety catch for the fifth wheel locking lever?

For a coupling to be completed, the safety catch for the fifth wheel locking lever must be: Over the locking lever. Why should you lock the air line glad hands to each other (or dummy couplers) when you are not towing a trailer? It will keep water out of the lines.

What should you hook up before backing under the trailer?

After connecting the air lines but before backing under the trailer you should: A Supply air to the trailer system, then pull out the air supply knob.

### What would happen if the emergency red air line between the tractor and trailer came apart?

Your emergency air line breaks or gets pulled apart while you are driving. The loss of pressure will cause the: Emergency trailer brakes come on. Why should you be sure that the fifth wheel plate is greased as required?

Why should you lock the glad hands or dummy couplers to each other when you are not towing another vehicle?

1. Why should you lock the tractor glad hands (or dummy couplers) to each other when you are not towing a trailer? A The connected brake circuit becomes a back up air tank.

#### What part of the king pin should the locking jaws close around?

shank
A The shank. Step 13 (Inspect Coupling): Go under trailer and look into the back of the fifth wheel. Make sure the fifth wheel jaws have closed around the shank of the kingpin.

Why should you lock the tractor glad hands?

## What is a fifth wheel coupling?

Fifth Wheel Coupling. A “fifth wheel coupling” is a device that connects the tractor with the trailer. The mechanism is simple and can easily be removed. It adjusts and supports the front and rear load of the trailer, which makes safe trailer transportation possible.

What is a fifth wheel skid plate?

Fifth wheel is the name of the assembly. fifth wheel plate or skid plate are used interchangeably by different people. What you are looking for is this…. No gap between the apron and skid plate. Skid plate is not bent, cracked or broken. Jaws are latched securely around the kingpin. There is no missing,…

### What is a hydraulic fifth wheel?

Ottawa Yard Truck Hydraulic Valve for Fifth Wheel (Part #90016497) The hydraulic system is powered by a power take off (PTO) which is bolted on the side of the transmission and is ran off the gears inside the transmission. The PTO has a hydraulic pump bolted to it with a shaft that has splines that fit into the PTO.

What is a 5th wheel tractor?

A tractor-trailer fifth wheel along with a kingpin provides the coupling link between the truck cab and the semi-trailer it will be hauling. Despite its name, the 5 th wheel is a horseshoe-shaped coupling device while the kingpin is a, roughly,…