3-4
F-473-0212 Edition
OPERATING INSTRUCTIONS
Coupling of the Tractor to the
Semitrailer
DANGER
1.
Verify the semitrailer wheels are chocked and brakes
function properly.
2.
Make certain the coupler of the towing vehicle’s fifth
wheel is open by pulling the latch handle.
3.
Slowly back the towing vehicle so its fifth wheel
contacts the front of the king pin plate on the
semitrailer and slips under it. Continue backing until
the fifth wheel coupler locks onto the semitrailer
kingpin.
CAUTION
4.
Verify the vehicle coupling is secure by attempting to
pull the tractor forward a few inches. If the tractor
disconnects from the semitrailer, locate source of
coupling failure; repair before continuing; and repeat
5.
Check that the towing vehicle couples securely to the
semitrailer before setting towing vehicle and
semitrailer parking brakes.
IMPORTANT
Keep brakes engaged for remainder of hookup,
checkout procedures and parking.
Connecting Tractor Services to
the Semitrailer
1.
Connect the towing vehicle 7-pole electrical plug to
the electrical receptacle on the front of the semitrailer
IMPORTANT
The key on the plug and the keyway in the socket
must be properly aligned before inserting the plug
into the semitrailer socket.
CAUTION
2.
If you have not already done so, connect the tractor
hydraulic lines to the semitrailer unless your
semitrailer is equipped with the self-contained
hydraulic power engine package.
IMPORTANT
Some oil may need to be removed from the tractor
reservoir to allow room for 2 gallons of additional oil
displaced from the trailer hydraulic system.
3.
Air Lines:
(See “Pre-Coupling of Semitrailer and
Keep all personnel clear of front, rear, and sides
of towing vehicle and semitrailer during coupling,
component operations, and uncoupling. Failure
to stay clear can result in serious personal injury
or death.
Pushing the semitrailer backwards can damage
parking stands.
Hydraulic operating pressures greater than 2500
psi can cause damage to the trailer.
