TM 5-3825-229-14&P
2-6. COUPLING SEMITRAILER TO TOWING VEHICLE (cont)
b. Slowly back the towing vehicle into position. Be sure the kingpin is in line with the fifth wheel coupler jaws.
c. Stop the towing vehicle just before the kingpin plate of the semitrailer starts to ride up the approach ramps of the
towing vehicle.
d. Check that kingpin plate is above the rear of the approach ramps before kingpin plate begins to ride up approach
ramps. Adjust height as needed by using landing gear. Be sure that the towing vehicle fifth wheel coupler jaws are open.
e. Slowly back the towing vehicle until coupler jaws engage the kingpin.
CAUTION
Visually check the coupling. You should not be able to see light between the fifth wheel and
kingpin plate. If coupling is not complete and another attempt is to be made, move towing vehicle
forward carefully. Do not exceed the limits of the air hoses and electrical cable.
f. Make sure coupling is secure by inching towing vehicle forward. If coupling is not locked, rock towing vehicle
back and forth slowly until kingpin is locked in fifth wheel.
g. Connect the two air hoses marked SERVICE and EMERGENCY on the towing vehicle to the corresponding air
hose couplings in the semitrailer.
h. Open air line shutoff valves on towing vehicle.
i.
Set the trailer handbrake to lock the trailer wheels
NOTE
An additional safety measure is to chock the semitrailer wheels against movement or accidental trailer brake failure.
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