freightliner Cargo Manual page 110

Fifth Wheels
throat of the locking mechanism. See
just the trailer landing gear to give enough align-
ment height so that the fifth wheel picks up the
trailer on the fifth wheel ramps.
4. With the fifth wheel lock opening aligned with the
trailer kingpin, back the tractor slowly toward the
trailer, making sure that the kingpin correctly enters
the throat of the locking mechanism. When the
trailer is picked up by the fifth wheel, stop the trac-
tor, then resume a slow backward motion until posi-
tive lockup occurs.
5. Apply the tractor parking brakes.
6. Make a visual check for proper kingpin lockup. Re-
lease the tractor parking brakes.
Test for kingpin lockup by pulling on the trailer
against the chocks. Check for correct maximum
clearance between the lock halves. If more than
1/8-inch (3.2-mm) clearance exists between the
lock halves, the lock must be adjusted. Refer to
Group 31 of the Cargo Workshop Manual for ad-
justment procedures.
WARNING
Adjust the locks correctly to a maximum clearance
of 1/8 inch (3 mm). Incorrect adjustment of the lock
11.3
Fig. 11.3. Ad- could cause the trailer to disconnect, possibly re-
sulting in serious personal injury or death.
7. After lockup is completed, connect the tractor-to-
trailer air system lines and electrical cable to the
trailer. Take care to prevent dirt or foreign material
from entering the air lines.
8. Charge the air brake system with air. Make sure
that the air connections do not leak.
9. Retract the trailer landing gear and secure the
ratchet handle.
10. Remove the chocks from the trailer tires.
11. The 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 weigh-
ing the vehicle on scales designed for this purpose.
The maximum axle weight ratings are shown 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 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 rating given on the FMVSS
or CMVSS label.