Automatic Application
E210345
If both knobs (A and B) are pushed in and
the brake system air pressure is reduced
to approximately 35 psi (249 kPa), the
trailer air supply (A) knob automatically
pops out applying the emergency or
parking brakes on the trailer. If the trailer
air supply (A) knob is manually held in and
the air pressure is reduced to
approximately 30 psi (207 kPa), a tripper
piston within the valve moves, exhausting
the trailer air supply, applying the trailer
brakes. Further reduction of air pressure,
while holding the trailer air supply knob in,
causes the parking brake knob to pop out
at 25 psi (172 kPa).
Actuation of Trailer Park (Emergency)
or Tractor Bobtail Position
E210345
To actuate the trailer brakes only, pull out
the trailer air supply (A) knob. This applies
the trailer brakes whether the trailer uses
emergency or spring brakes.
You can also use this mode when the
tractor or truck with trailer is used during
bobtail operation.
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Brakes
The system may apply the brakes to slow
the vehicle to the new set speed. The set
speed displays continuously in the
information display when the system is
active.
Canceling the Set Speed
E265298
Press and release the button or
tap the brake pedal.
The set speed does not erase.
Resuming the Set Speed
Press and release the button.
Your vehicle speed returns to the
previously set speed and gap setting. The
set speed displays continuously in the
information display when the system is
active.
Note:Only use resume if you are aware of
the set speed and intend to return to it.
Automatic Cancellation
The system is not functional at vehicle
speeds below 12 mph (20 km/h). An
audible alarm sounds and the automatic
braking releases if the vehicle drops below
this speed.
Automatic cancellation can occur when
the tires lose traction or you apply the
parking brake.
Note:If your vehicle speed drops too low,
an audible warning sounds and a message
appears in the information display.
Automatic braking releases.
Hilly Condition and Trailer Tow
Usage
You should select a lower gear when the
system is active in situations such as
prolonged downhill driving on steep
grades, for example in mountainous areas.
The system needs additional engine
braking in these situations to reduce the
load on the vehicle’s regular brake system
to prevent it from overheating.
Note:An audible alarm sounds and the
system shuts down if it applies brakes for
an extended period of time. This allows the
brakes to cool. The system functions
normally again after the brakes cool.
Note:When towing with adaptive cruise
control, switch on Diesel engine brake.
Switching Adaptive Cruise Control
Off
E265297
Press and release the button
when the system is in standby
mode, or switch the ignition off.
Note:The set speed and gap setting is
erased when you switch the system off.
Detection Issues
WARNING: On rare occasions,
detection issues can occur due to the
road infrastructures, for example bridges,
tunnels and safety barriers. In these
cases, the system may brake late or
unexpectedly. At all times, you are
responsible for controlling your vehicle,
supervising the system and intervening,
if required.
WARNING: If the system
malfunctions, have your vehicle checked
as soon as possible.
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Cruise Control - Vehicles With: Adaptive Cruise Control
• Shift to a lower gear when driving down
a long or steep hill. Do not apply the
brakes continuously, as they may
overheat and become less effective.
• If your transmission is equipped with
the Tow/Haul feature, use this feature
when towing. This provides engine
braking and helps eliminate excessive
transmission shifting for optimum fuel
economy and transmission cooling.
• Allow more distance for stopping with
a trailer attached. Anticipate stops and
brake gradually.
FIFTH WHEEL OPERATION
WARNING: Failure to follow the
fifth wheel manufacturer’s instructions
for hooking and unhooking as well as
sliding the fifth wheel could result in an
accident, personal injury or death.
WARNING: When the tractor and
trailer are parked unattended, the trailer
brake hand control should never be used
to apply the brake, since air may leak
from the system, allowing vehicle
movement, resulting in possible property
damage, personal injury or death.
Before hook-up, make sure:
• The fifth wheel jaws are fully open.
• The fifth wheel is fully tilted back to
prevent body damage when the tractor
is backed under a trailer.
• You block the trailer wheels and adjust
and apply the trailer spring brakes.
Never chase a trailer.
• The brake hoses and light cords are
clear of the fifth wheel.
Hook-up
1. Back the tractor squarely under the
trailer, engaging the fifth-wheel jaws
on the kingpin. Always back up slowly;
make sure the trailer is neither too high
nor too low. Avoid backing under the
trailer from an angle.
2. Connect the service and emergency
brake hoses and trailer light connector.
3. Inspect the jaws of the fifth wheel to
be sure they have fully closed on the
trailer kingpin and the trailer plate is
resting securely on the fifth wheel.
4. Make sure the coupler release lever is
in the locked position.
5. Charge the trailer brake system. Set
the trailer brakes, with either the hand
valve or tractor protection valve. Pull
against the trailer for an extra check of
proper hook-up. Do not pull hard
enough to damage or strain the
equipment.
6. Set the tractor parking brakes and fully
raise the trailer landing gear.
7. Check the operation of all trailer lights
and correct any lights that may be
faulty.
Un-hook
1. Try to keep the tractor and trailer in a
straight line.
2. Apply the parking brakes.
3. Lower the trailer landing gear, making
sure it is on solid, level ground. The
weight of the trailer is to be on the
landing gear.
4. Block the trailer wheels.
5. Disconnect the brake hoses and light
cords. Be sure hoses and cords are
clear.
6. Pull coupler release lever to disengage
the fifth wheel jaws.
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Towing
7. Release the tractor parking brakes.
8. Pull out from the trailer slowly, allowing
the landing gear to take the load
gradually.
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Towing
GENERAL DRIVING POINTS
General Information
• Accelerate smoothly and evenly. Rapid
acceleration increases fuel
consumption without increasing engine
performance.
• When approaching a hill, press the
accelerator smoothly to start the
incline at full power, and then shift
down as needed to maintain vehicle
speed.
• When going down a hill, or long steep
grades, prevent overspeeding of the
engine. Normally, choose the same
gear to descend the hill that you use to
ascend the hill. The engine governor
has no control over engine speed when
it is being pushed by a loaded vehicle.
• Do not operate in a gear that permits
an engine speed more than the
maximum governed speed or high-idle
RPM (no load).
• Always shift to a lower gear at high
altitudes to prevent engine smoking.
Backing Up
WARNING: All vehicles have blind
spots. To reduce the risk of severe injury
or property damage, never move your
vehicle to the side or rear or change lanes
without being sure your way is clear on
both sides and to your rear.
WARNING: To reduce the risk of
the possibility of personal injury while
backing up the vehicle, always be sure
your vehicle’s path is clear.Before backing up your vehicle, be sure you
can do so safely. If anything behind the cab
limits your view, do not rely on mirrors
alone to make sure that your intended path
is clear. If other people are in the vicinity,
have someone standing well behind your
vehicle and outside of your intended path
(visible through an exterior mirror) guide
you as you back up.
Although OSHA or some governmental
regulations may require the use of an
electrical or mechanical back up alarm to
warn bystanders, such an alarm does not
guarantee that the intended path is clear.
When in doubt, get out of your vehicle and
visually check the intended path is clear.
Back up slowly as to allow others time to
move, if necessary.
If you install an electrical back up alarm,
connect it to the backup lamp circuit.
Parking
WARNING: When parking your
vehicle, do not leave the transmission in
gear; if the key is in the on position and
the vehicle rolls, the engine could start.
Failure to follow these instructions could
result in an unattended vehicle moving,
possibly causing personal injury or
property damage.
Always use the parking brake. When
parking on a grade, block the wheels and
turn the front wheels to one side so that if
your vehicle rolls, the front tires act against
the curb to stop your vehicle. The front
wheels are more effective at stopping a
rolling vehicle than the rear wheels.
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Driving Hints
VEHICLE INSPECTION
INFORMATION
To make sure your vehicle is ready to
operate, conduct a pre-trip inspection at
the beginning of each work period. Follow
the steps listed in this section to verify a
proper vehicle inspection procedure.
WARNING: Exercise great caution
when working on a vehicle equipped with
an automatic fan clutch. The fan starts
in motion only after the engine coolant
reaches a predetermined temperature
or the refrigerant pressure (if equipped
with air conditioning) reaches a
predetermined setting. The fan starts at
this point with no advance warning.
Never reach near, or permit objects to
protrude into, the fan blade radius while
the engine is running as this could result
in vehicle damage, personal injury or
death.
WARNING: Do not operate the
vehicle if any suspension conditions
listed in the following charts are evident.
Loss of steering or suspension could
result in property damage, personal injury
or death.
WARNING: If a wheel must be
changed, obtain expert tire service help.
Mounting and un-mounting of tires
should only be performed by a qualified
technician using necessary safety
procedures and equipment, otherwise
the result could be property damage,
personal injury or death.
Note:Always make sure you apply the
parking brake before starting the engine.
Engine compartment (with engine off)
Use the dipstick to verify the oil level is in the proper operating
range. See Engine Oil Dipstick (page 224). Engine oil
Look through the plastic reservoir and verify the coolant level
is within the proper operating range. Do not remove the
pressure cap until the coolant has cooled. See Engine
Coolant Check (page 238). Engine coolant
Verify that the fluid level is in the proper operating range. See
Power Steering Fluid Check (page 245). Power steering fluid
Remove the master cylinder caps and inspect the fluid level.
See Brake Fluid Check (page 244). Brake fluid
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Vehicle Inspection Guide
Engine compartment (with engine off)
Inspect for glazing, fraying or cracking. There should be no
more than 5-7 cracks per rib, per 1 in (2.5 cm) Belts (fan, alternator,
water pump and air
conditioning
compressor)
Inspect for signs of fluid puddles or dripping fluid on the
ground under the engine, or the underside of the engine. Fluid leaks
Inspect for debris that may have collected on the HVAC air
inlet grille or inside the exterior module as this may reduce
system performance. HVAC air inlet
Engine starting (with parking brake applied)
Before entering the cab, verify that the vehicle is equipped
with spare electrical fuses (if used), three red reflective
triangles, a properly charged and rated fire extinguisher and
wheel chocks. Safety and emergency
equipment
Walk around the vehicle and verify all steps and grab handles,
inside and out (as well as behind), are tight and clean. Use
extreme caution and a three-point stance at all times.
Inspect door latches for proper closing, latching and locking.
Set the parking brake. Make sure the gearshift lever is in
neutral (N) or park (P) (if equipped with a park position). Starting the engine
Diesel engine: Turn the key to the on position. Turn the key
to start when the wait to start indicator light in the instrument
cluster turns off.
Gasoline engine: Turn the key to start, and then release it
as soon as the engine starts.
Verify pressure builds to normal operating range. Engine oil pressure
A tone indicating low air pressure should sound immediately
after the engine starts but before the compressor has built-
up pressure. The tone should stop when the air pressure
reaches 70 psi (483 kPa). Let the air pressure build to
governed cutout pressure, which should occur between
115–130 psi (793–896 kPa). Low air pressure warning
tone (if equipped with an
air compressor)
Press the accelerator and verify that it operates smoothly,
without any binding or irregular feel. Release the pedal and
verify the engine returns to idle speed immediately. Accelerator
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Vehicle Inspection Guide
Engine starting (with parking brake applied)
Check the gauge (diesel engine) or indicator light (gasoline
engine) to verify the alternator is charging. Voltmeter
Inspect for excessive free play in the steering linkages. The
steering wheel should have less than 2 in (5 cm) of free play
at its rim. Steering linkage free play
Verify the parking brake holds the vehicle by gently trying to
pull forward with the parking brake applied. Parking brake
Verify operation using the following procedure. Chock the
wheels, if necessary. Push in the parking brake and, on
tractors, push in the tractor parking brake knob: Air brakes
1. Verify the air compressor or governor cutout pressure is
approximately 120 psi (827 kPa).
2. Turn off the engine, and then turn the key back to the on
position (without starting the engine).
3. Without the brake pedal applied, note the air pressure drop
for one minute. It should be less than 2 psi (14 kPa) for single
vehicles and 3 psi (21 kPa) for combination vehicles.
4. Press and hold the brake pedal with 90 psi (621 kPa) or
more. Make sure there is no more than a 3 psi (21 kPa) per
minute leak for single vehicles and a 4 psi (28 kPa) minute
leak for combination vehicles.
5. Pump the brake pedal to deplete the system of air pressure.
The warning light and tone should turn on at 57 psi (393 kPa).
6. Pump the brake pedal and make sure the parking brake
and trailer parking brake knobs pop out at 20 psi (138 kPa)
or higher.
Verify that the fluid level is in the proper operating range. See
Automatic Transmission Fluid Check (page 242). Automatic transmission
fluid
Front of vehicle
Verify all exterior lights illuminate and are clean. Lights
Check headlights function on high and low beam.
Verify reflectors are clean, unbroken and of proper color (red
on rear, amber elsewhere).
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Vehicle Inspection Guide