UNCOUPLING
1. Position yard spotter tractor and trailer on firm,
level ground — clear of obstructions and people.
2. Set trailer brakes, lower fifth wheel until
the trailer landing gear touch the ground.
Set tractor brakes.
3. Block trailer wheels. Disconnect trailer
air supply and electrical connection.
4. If the manual secondary lock was engaged,
remove the hairpin clip on the secondary lock
handle, pull the secondary lock handle out-
ward to disengage the secondary lock. While
holding the handle out, re-insert the hairpin
clip into the hole in the handle on the outside
of the handle guide. (See
FIGURE 5
.)
5. Actuate the fifth wheel control valve and hold
it in to open the locks.
6. While holding the lock control valve in, slowly
pull out from the trailer.
7. After driving completely free of the kingpin,
release the lock control valve.
All elevating fifth wheels
— when towing trailers
in the elevated position —
are less stable than
conventional tractor-trailers
and are sensitive to speed
and maneuvers.
This unit is not recommended for operation on
public streets and highways. When such trailer
moves are necessary, the manual secondary
lock on the fifth wheel must be engaged (see
coupling procedure #5 at left) and the fifth
wheel must be in the down position. Limit
speed to 45mph maximum.
WARNING
4. Back under the trailer and engage the fifth
wheel locks with the trailer kingpin. Pull for-
ward to test the completeness of the coupling
as an INITIAL check. Set tractor brakes. Next,
visually
inspect the fifth wheel, as shown in
FIGURE 3
, to verify that it is properly locked.
5. If operation on public streets or highways is
required, the manual secondary lock must be
engaged. To engage the secondary lock, re-
move the hairpin clip on the secondary lock
handle allowing the secondary lock to pivot
and engage behind the locking yoke as shown
in
FIGURE 4
.
6. Remove blocks. Retract the landing gear, if nec-
essary. Release trailer and tractor brakes. Raise
trailer to desired height and move trailer.
WARNING
Failure to verify a proper
couple can result in tractor
and trailer separation causing
death or serious injury to
you or others.
LOCKS COMPLETELY CLOSED AROUND KINGPIN
View looking into the throat of the fith wheel
Bolster plate is flush
with the fifth wheel
FIGURE 3
SECONDARY LOCK DISENGAGED
MANUAL
SECONDARY
LOCK
HANDLE
SECONDARY LOCK
DISENGAGED
MANUAL
SECONDARY
LOCK HANDLE
GUIDE
2
SECONDARY LOCK
ENGAGED
MANUAL
SECONDARY
LOCK HANDLE
SECONDARY
LOCK ENGAGED
FIGURE 4
FIGURE 5
XL-FW313-01 Rev C
