Daimler Freightliner Cascadia 2021, Driver Manual

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Preparing the Trailer for Uncoupling
Before using the air valve to unlock a fifth wheel
kingpin, prepare the trailer as follows.
1.
Apply the tractor and trailer parking brakes.
2. Chock the trailer rear wheels.
3.
Lower the trailer landing gear until the weight is
removed from the fifth wheel.
4. Disconnect the tractor-to-trailer air lines and elec-
trical cable. Plug the air lines to prevent dirt or
foreign material from entering the lines.
Air-Activated Kingpin Unlock
1. Verify that both the yellow parking-brake and red
trailer-air supply knobs are out, the tractor and
trailer parking brakes are set, and that the trailer
is prepared for uncoupling.
NOTE: The kingpin release will not actuate if the
switch is pushed for less than 3 seconds, the
vehicle is moving, or the parking brake is not
set. Unless all these conditions are met, the
trailer is not uncoupled and an alert is shown on
the driver display.
2. Push and hold the kingpin release switch
(
Fig. 20.9 ) for a minimum of 3 seconds. The sys-
tem will apply air for 20 to 30 seconds to ensure
the kingpin unlocks. When the kingpin is un-
locked, a notification is displayed; see
Fig. 20.10 .
3. Release the tractor parking brake.
4. Drive out from under the trailer.
Fifth Wheel Slide
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.
On sliding fifth wheel assemblies, the fifth-wheel
plate is attached to rails that allow forward and rear-
ward movement of the fifth wheel to optimally distrib-
ute the load across the axles. Slots are evenly
spaced along the slide rails, and retractable wedges
are positioned through the slots to hold the fifth
wheel in the desired position.
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 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.
Manual Slide Operation
The manual slide feature is operated from the fifth
wheel plate with a manual release handle using the
following procedure. See
Fig. 20.11 .
f611341 03/09/2016
K−PIN
REL
Fig. 20.9, Kingpin Release Switch
f611426 06/14/2016
Fig. 20.10, Kingpin Release Alert Screen
Fifth Wheels
20.6