OPERATING PROCEDURES (Continued)
Coupling to Trailer (continued).
Shift to neutral and operate 5th WHEEL lever to obtain the proper coupling height, as illustrated.
Pull out PARKING BRAKE valve to apply tractor spring brakes.
Pull TRAILER AIR SUPPLY valve out, connect service and emergency air hoses and electrical cable to
Push TRAILER AIR SUPPLY valve in and pull hand brake control to set trailer service brakes.
Shift to reverse and release tractor brakes.
(10) Slowly back tractor under the trailer until fifth wheel jaws engage the trailer kingpin and lock automatically.
(11) Test coupling: shift transmission into a forward gear, release tractor brakes, and increase engine RPM
slightly. Then, return gear shift lever to neutral (N) position.
(12) With tractor brakes released, pull back 5th WHEEL lever to raise trailer to maximum height.
Trailer lifting speed may be increased by accelerating tractor engine. Fifth wheel boom will not raise
unless PTO is engaged and transmission is in neutral.
If receptacle and cable for 24-volt trailers is used, push 24V INVERTER switch up to turn on inverter.