Daimler Freightliner Cascadia 2021, Driver Manual

Page: 262 / 322

10. After lockup is completed, connect the tractor-to-
trailer air system lines and the electrical cable to
the trailer. Take care to prevent dirt or foreign
material from entering the air system lines.
NOTICE
Always make sure the connection hanger keeps
the trailer air hoses and electrical cables posi-
tioned so that they do not rub on anything. Rub-
bing may wear through hoses or cables, resulting
in air leaks, or exposed or broken wires, poten-
tially affecting trailer brake or electrical systems.
11. Charge the air brake system with air, checking
that the air connections do not leak.
WARNING
Incorrect fifth wheel lock adjustment could cause
the trailer to disconnect, possibly resulting in se-
rious personal injury or death.
12. With the trailer wheels chocked and the brakes
set, check for clearance between the kingpin and
the fifth wheel jaws by moving the tractor forward
and backward against the locked kingpin. If slack
is present, uncouple the trailer and have the fifth
wheel inspected and adjusted by a certified
technician.
Jost Fifth Wheel Coupling
1. Tilt the ramp down.
2. Open the kingpin locks. See Fig. 20.6 .
3. Back the vehicle close to the trailer, centering the
kingpin on the fifth wheel.
4.
Chock the trailer wheels.
5. Connect the air lines and electrical cable.
6.
Ensure that the red trailer air supply valve (trailer
brake) is pulled out, and that the trailer parking
brakes are set. See Chapter 4 in this manual for
operation of the dash-mounted brake controls.
NOTICE
Attempting to couple at the wrong height may
cause improper coupling, which could result in
damage to the fifth wheel or kingpin.
7. Adjust the trailer height (if required).
For a standard fifth wheel plate , the trailer
should contact the fifth wheel approximately 4 to
8 inches (10 to 20 cm) behind the pivot. See
Fig. 20.3 .
For a low-lube fifth wheel plate , the fifth wheel
must slide freely under the trailer, and the trailer
should contact the fifth wheel at the pivot. See
Fig. 20.4 .
8. Back the tractor under the trailer.
On a standard fifth wheel, the fifth wheel must lift
the trailer.
On a low-lube fifth wheel, do not lift the trailer as
this may damage the fifth wheel plate.
9.
After sliding under the trailer, STOP to prevent
from hitting the kingpin too hard, then resume
backing slowly until the fifth wheel locks.
WARNING
A visual inspection is required by law. Some im-
proper couplings can pass a pull test. Sound is
not reliable. Get out of the cab and look. Incor-
rect coupling could cause the trailer to discon-
nect, possibly resulting in serious personal injury
or death.
f311126 04/28/2017
A B
A. No gap between trailer
and fifth wheel
B. Kingpin inside lock
Fig. 20.5, Coupling Inspection
f311128 04/28/2017
A
A. Lock held open by catch mechanism
Fig. 20.6, Jost Release Handle Unlocked
Fifth Wheels
20.3