freightliner CENTURY CLASS S Driver Manual page 174

Fifth Wheels and Trailer Couplings
6. Slowly move the tractor forward or backward
until the fifth wheel is in the desired location.
7.
Apply the tractor parking brakes.
NOTE: The fifth wheel may have to be moved
slightly to enable the locking wedges to enter
the fully locked position.
8. Lock the sliding member in position using one of
the following methods:
WARNING
Check to be sure that the lockpins are seated in
the holes. Failure to achieve complete lockup
may cause the trailer to detach from the tractor,
possibly resulting in serious personal injury or
death.
8.1 For air-operated release models, set the
cab-operated slide control switch to
LOCK. Visually inspect the locking
wedges to make sure that they are fully
inserted in the slide rail slots.
8.2 For manual release models, disengage
the slide release pull handle from the
guide plate. The slide release pull handle
is spring-loaded in the locked position and
will seek the locked position when disen-
gaged from the guide plate. The fifth
wheel may have to be moved slightly to
enable the locking wedges to fully enter
the locked position. When the slide re-
lease pull handle returns to the fully
locked position, visually and physically
check the locking wedges to make sure
they are fully inserted into the slots in the
slide rails. Make sure the slide release pull
handle is locked in position against the
guide plate.
9.
The amount of load distribution on the front
steering axle and rear drive axle(s) will have a
direct effect on the steering control of the vehicle.
Determine the front and rear axle weights by
weighing the vehicle on scales designed for this
purpose.
The maximum axle weight ratings are given on
the Federal Motor Vehicle Safety Standard
(FMVSS) label or Canadian Motor Vehicle Safety
Standard (CMVSS) label attached to the left rear
door post of the tractor. The desired load on the
10.15
axle is no less than 80 percent of the maximum
axle weight rating, but in no instances should the
axle load exceed the maximum axle weight rat-
ing given on the FMVSS or CMVSS label.
WARNING
Adjust the fifth wheel slide correctly, and do not
overload any tractor axle by incorrectly loading
the trailer. Incorrect slide adjustment or improper
axle loading could cause erratic steering and
loss of vehicle control, possibly resulting in seri-
ous personal injury or death.
Fifth Wheel Lubrication
WARNING
Keep the fifth wheel plate lubricated to prevent
binding between the tractor and trailer. A binding
fifth wheel could cause erratic steering and loss
of vehicle control, possibly resulting in serious
personal injury or death.
For lubrication instructions, see Group 31 of the
Century Class Trucks Maintenance Manual .
Premier Trailer Couplings
IMPORTANT: Before operating the Premier cou-
pling, refer to the Premier web site at
www.premier-mfg.com
operation, and maintenance instructions.
General Information
Trailer couplings, used only on trucks, are attached
to the rear closing crossmember.
The Premier 260 and 460 trailer couplings
(Fig. 10.18) have a rigid pintle hook, and are air-
adjusted. An air chamber, mounted forward of the
coupling, operates a pushrod, which pushes against
a shoe inside the coupling. The shoe maintains con-
stant pressure on the eye of the trailer drawbar when
it's over the pintle hook. This takes up any slack in
the trailer connection, providing smoother towing and
less wear on the pintle hook. The air pressure is acti-
vated when the trailer brakes are released.
The Premier 690 trailer coupling
moveable pintle hook, and is non-air adjusted. It is
used for heavy-duty applications.
for complete safety,
(Fig. 10.19) has a