Kingpin And Oscillating Fifth Wheel Plate - Midland SIDE DUMP GRAVEL TRAILER Operator's Manual

5.2.2

KINGPIN AND OSCILLATING FIFTH WHEEL PLATE

The kingpin at the front of the trailer is the structural
component used to transmit accelerating and
decelerating loads into the trailer frame. It must be in
good condition to perform as required.
Visually inspect the kingpin as part of
the pre-trip inspection, at 5,000 miles
(8,000 km) or weekly and annually
as part of your normal preventative
maintenance program. Be sure the
kingpin does not have excessive wear,
looseness, chipped out areas, cracks
or bent mounting frame. If any kingpin
shows such defects, it should be
replaced immediately.
Visually inspect the frame and structure of the
mounting frame for bends, cracks or distortions as
part of the pre-trip inspection procedure. Thoroughly
inspect the structural integrity of the assembly every
25,000 miles (40,000 km) or every three months as
part of your preventative maintenance program.
Repair the mounting frame if any structural defects
are found.
Fig. 41 KINGPIN
IMPORTANT
If a lube plate is used in your
operation, make sure to check
the kingpin length. The kingpin
must be sized to compensate for
the thickness of the lube plate.
Otherwise, the kingpin will be
too short. If the kingpin length is
improper, the kingpin should be
replaced.
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