Fifth Wheel Slide Operation
- Connect the trailer kingpin to the tractor fifth wheel. For instructions, refer to Holland "Fifth Wheel Locking Operation" in this chapter.
- After positive lockup of the fifth wheel lock mechanism
has been accomplished, release the sliding member using one of the
following methods:
- For air-operated models, set the cab-operated control
switch (see Fig.) to UNLOCK.
Fig. 1, Cab Control, Fifth Wheel Slide
- For manual release models, pull the release lever (see
Fig.) using a release hook, or other suitable tool. Make sure
both slide plungers have released. See Fig.. If the plungers have
not released (come out), lower the trailer landing gear to relieve
pressure on the plungers.
Note: Baseplate rails not shown.
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Kingpin Lock Control Handle
-
Plunger Release Handle
-
Plunger Release Spring
-
Plunger
Fig. 2, Manual Release Slide
-
Locked (engaged)
-
Unlocked (released)
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Plunger
Fig. 3, Plunger Positions
-
- For air-operated models, set the cab-operated control
switch (see Fig.) to UNLOCK.
- Lower the trailer landing gear just enough to remove the weight from the tractor.
- Pull the trailer air supply valve to cut off the air supply to the trailer.
- Chock the front and rear of the trailer tires to prevent the trailer from moving.
- Slowly move the tractor forward or backward until the fifth
wheel is in the desired location.
- Apply the tractor parking brakes.
- Lock the sliding member into position using one of the
following methods:
- For air-operated models, set the cab-operated control
switch to LOCK. Visually check the slide plungers to make sure they
are engaged in the fully locked position. See Fig..
- For manual release models, trip the release lever (see Fig.) using a release hook or other suitable tool. Make sure that both plungers have locked (retracted into their pockets), and are fully engaged in the rack teeth. See Fig.. It may be necessary to move the tractor slightly while keeping the trailer brakes locked.
Warning: Check to be sure that the slide plungers are in the locked position. Failure to achieve complete lockup may allow disengagement of the tractor from the trailer, possibly resulting in serious personal injury or death.
- For air-operated models, set the cab-operated control
switch to LOCK. Visually check the slide plungers to make sure they
are engaged in the fully locked position. See Fig..
- The amount of load distribution on the front steering axle
and rear drive axle(s) will have a direct effect on the steering control
of the vehicle.
Determine the front and rear axle weights by weighing the vehicle on scales designed for this purpose.
The maximum axle weight ratings are shown on the Federal Motor Vehicle Safety Standard (FMVSS) label or Canadian Motor Vehicle Safety Standard (CMVSS) label attached to the left rear door post of the tractor. The desired load on the axle is no less than 80 percent of the maximum axle weight rating, but in no instances should the axle load exceed the maximum axle weight rating given on the FMVSS or CMVSS label.
Warning: Do not overload any tractor axle by improperly loading the trailer. This could cause erratic steering and loss of vehicle control, possibly resulting in serious personal injury or death.
Warning: Do not use the trailer air supply for parking trailers not equipped with spring parking brakes. This applies the trailer service brakes only. As air bleeds from the trailer brake system, brake application is lost. This could allow the unattended vehicle to roll away, possibly resulting in serious personal injury or death.
Notice: After moving the fifth wheel to the desired position, be sure the trailer landing gear will not, at any time, come in contact with the tractor frame or other components. Make sure that the front of the trailer will not come in contact with the rear of the cab or with other components if they extend beyond the rear of the cab.
Note: The fifth wheel may have to be moved slightly to enable the locking plungers to enter the fully locked position.