
ABS warning lamp
The
ABSwarning lamp in the instrument cluster momentarily illuminates
when the ignition is turned on and the engine is off. If the light does not
illuminate momentarily at start up, remains on after the vehicle reaches
10 to 15 km/h (5 to 10 mph), or continues to flash, the ABS needs to be
serviced.
With the ABS light on, the anti-lock brake system is disabled and normal
braking is still effective unless the brake warning light also remains
illuminated. (If your parking brake warning lamp illuminates, have your
vehicle serviced immediately).
Using ABS
•In an emergency or when maximum efficiency from the ABS is
required, apply continuous full force on the brake. The ABS will be
activated immediately, thus allowing you to retain full steering control
of your vehicle and, providing there is sufficient space, will enable you
to avoid obstacles and bring the vehicle to a controlled stop.
•The ABS does not decrease the time necessary to apply the brakes or
always reduce stopping distance. Always leave enough room between
your vehicle and the vehicle in front of you to stop.
•We recommend that you familiarize yourself with this braking
technique. However, avoid taking any unnecessary risks.
TRACTION CONTROL(IF EQUIPPED)
Your vehicle may be equipped with a Traction Controlsystem. This
system helps you maintain the stability and steerability of your vehicle,
especially on slippery road surfaces such as snow- or ice-covered roads
and gravel roads, by reducing engine power and/or selectively applying
the rear brakes. The system will allow your vehicle to make better use of
available traction in these conditions.
Note:The traction control system will not apply the brakes when the
vehicle speed is above 40 km/h (25 mph).
During Traction Controloperation,
the traction control light in the
instrument cluster will flash and the
engine will not“rev-up”when you
push further on the accelerator. This
is normal system behavior and should be no reason for concern. If the
traction control light does not flash or stays illuminated, the system is
not functioning.
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When operating a loaded vehicle, the driver must keep all
adjustable axles on the ground at all times, supporting their
share of the vehicle’s load. Failure to do so can overload other axles,
tires, wheels, springs, steering components, brakes and frames,
resulting in early component failure, loss of vehicle control, possible
property damage and personal injury.
FIFTH WHEEL OPERATION
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.
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.
Hook-up
1. Fifth wheel jaws must be fully opened.
2. Tilt the fifth wheel back to prevent body damage when the tractor is
backed under a trailer.
3. Block the trailer wheels and be sure the trailer spring brakes are
adjusted and applied. Never chase a trailer.
4. Make sure the brake hoses and light cords are clear of the fifth wheel.
5. Back the tractor squarely under the trailer, engaging the fifth wheel
jaws on the kingpin. Always back-up slowly, making sure the trailer is
neither too high nor too low. Avoid backing under the trailer from an
angle.
6. Connect the service and emergency brake hoses and trailer light
connector. Refer toTractor-trailer connectionin this chapter, adhering
to the warning and using the three-point stance while connecting and
disconnecting the trailer.
7. 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.
8. Be sure the coupler release lever is in the locked position.
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9. Charge the trailer brake system. Set the trailer brakes, either with the
hand valve or tractor protection valve. Pull against the trailer for an
additional check of proper hook-up. Do not pull hard enough to damage
or strain the equipment.
10. Set the tractor parking brakes and fully raise the trailer landing gear.
Refer toBrakesin this chapter for proper operation of the parking brake
and trailer brakes.
11. 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.
7. Release the tractor parking brakes.
8. Pull out from the trailer slowly, allowing the landing gear to take the
load gradually.
AUTOMATIC TRANSMISSION OPERATION (IF EQUIPPED)
Main transmission, auxiliary transmission, transfer case and power
take-off (PTO) control shift patterns can be found on a placard or decal
on the driver’s sun visor, on the instrument panel or on the shift control
itself.
The main transmission control is used to select the various gear ratios or
speeds of the transmission. Selecting D (Direct Drive), does not change
the transmission gear ratio, but is used where the gear ratios in the main
transmission are adequate to handle the vehicle operation.
Hold the brake pedal down while you move the gearshift lever
between positions. If you don’t hold the brake pedal down, your
vehicle may move unexpectedly and cause property damage, personal
injury or death.
Allison 2000 automatic transmission
This transmission is available with a column-mounted gearshift lever. The
gear positions are displayed on the RNDL in the instrument cluster.
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If the engine speed is above idle when a gear is selected using the
shifter, the vehicle will not move. To move the vehicle, the shifter must
be moved to re-select a gear after the engine speed returns to idle.
Note:For more information regarding the Allison MD-WT, refer to the
separate Allison MD-WT Operator’s Manual.
Torque lock
If your vehicle is parked on an incline and P (Park) is not properly
engaged (The parking brake is not applied before the transmission is
shifted into P [Park]), the weight of the vehicle may generate an
excessive amount of torque on the park pawl. In this situation, it may be
difficult to shift the transmission out of P (Park). Hold the brake pedal
down while shifting out of P (Park), then release the parking brake.
Allison MD (Medium Duty) push-button shifter
To shift the transmission into R
(Reverse) or D (Drive), depress the
brake pedal, then press R or D, then
release the brake pedal. To select a
lower range when in D (Drive),
press the down-arrow button. To
select a higher range when in D
(Drive), press the up-arrow button.
To place the transmission in N
(Neutral), press N.
Automatic transmission operating temperatures
Allison 2000/2400–The sump/fluid reservoir temperatures should not
exceed 120°C (250°F). The converter temperature should not exceed
144°C (300°F).
Power take-off (PTO) operation with an Allison automatic
transmission (except MD applications and vehicles equipped with
a Caterpillar 3126E engine)
The power take-off can be operated while the vehicle is standing or
moving.
To engage the PTO, apply the brakes and shift to any gear other than N
(Neutral) - this stops the rotation of the PTO drive gear in the
transmission - then engage the PTO.
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If engagement is prevented by the gear teeth not meshing properly,
release the brakes and allow the vehicle to creep slightly - or shift the
selector to N (Neutral) and then back in gear. The PTO should never be
engaged by clashing the gear teeth. This may damage the PTO unit and
the transmission PTO drive gear teeth. This could result in further
damage to the transmission and PTO.
PTO operation with vehicle stationary
To operate the power take-off, stop the vehicle, idle the engine and set
the parking brake. Make sure the gear selector is in any forward drive
range, then engage the PTO. After the PTO is engaged for stationary
vehicle operation, move the range selector to N (Neutral). Increase the
engine speed until the desired power take-off operation speed is
obtained. To disengage the PTO after operation with the vehicle
standing, release the throttle, allow the drive equipment to come to a
stop, and then disengage the PTO.
When the PTO is operated with the vehicle stationary, the
transmission must be placed in N (Neutral) with the parking
brake set. If the transmission is not in N (Neutral) and is equipped
with a remote throttle control, an increase in engine speed can
overpower the parking brake and cause the vehicle to move, possibly
resulting in personal and/or property damage.
PTO operation while vehicle is moving
After the PTO is engaged for driven vehicle operation, shift to the
desired range and drive the vehicle. The speed of the PTO, during this
period of operation, will always maintain direct relation to vehicle speed.
PTO speed will decrease in relation to vehicle (transmission output)
speed as shifts to a higher gear occur. When operating the PTO while the
vehicle is moving, the PTO may be disengaged whenever it is no longer
required. When there is no load on the PTO gear, it can be pulled out of
engagement.
Power take-off (PTO) operation on vehicles equipped with a
Caterpillar engine
If your vehicle is equipped with a Caterpillar engine, the PTO will only
operate if the vehicle is in Neutral. This feature can be overridden by a
special service tool; see your dealer or service representative for more
information.
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Driver-controlled differential lock
To prevent the vehicle from moving when servicing the wheels, tires or
brakes, turn the engine off and raise all drive wheels of the locker
differential axle. Axles equipped with NoSPIN Detroit Locker differentials
deliver power to both wheels even when only one wheel is on the ground.
Failure to raise all drive wheels with this type of differential
could cause the vehicle to move unexpectedly, resulting in
property damage, personal injury or death.
Care should be taken to avoid sudden accelerations when both drive
wheels are on a slippery surface.
Sudden accelerations on slippery surfaces could cause the
wheels to spin, the vehicle to turn sideways on a crowned road
surface or in a turn, possibly resulting in loss of vehicle control and
personal injury.
Some Dana/Spicer drive axles have a driver-controlled differential lock.
The differential lock can lock or unlock the differential when the vehicle
is moving or stopped. When extra traction is required, the differential
lock will provide full power to both axles.
The differential can be locked or unlocked when the vehicle is moving at
a constant speed of less than 40 km/h (25 mph) and while the wheels
are not slipping. If the differential is locked and vehicle speed exceeds
40 km/h (25 mph), the differential will automatically unlock. Also, the
differential must not be locked when the vehicle is traveling down steep
grades and traction is minimal.
When the differential is locked, the vehicle’s turning radius will increase
(vehicle will“under-steer”)
Axle conversions
It is not recommended, or approved, for axle conversions to be
performed. However, it is understood that, on occasion, aftermarket
add-on axles are installed by others on the truck chassis which allow
operator control for weight transfer from other axles (i.e., air lift axles).
When operating a loaded vehicle, the driver must keep all
adjustable axles on the ground at all times, supporting their
share of the vehicle’s load. Failure to do so can overload other axles,
tires, wheels, springs, steering components, brakes and frames,
resulting in early component failure, loss of vehicle control, possible
property damage and personal injury.
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•Canada
Under no circumstances should your vehicle be loaded in excess of the
GVWR or GAWR. It is the operator’s responsibility to assure that neither
the axle capacities, spring capacities, tire capacities nor the vehicle rated
GVWR is exceeded. For tire capacities, refer toMaintenance and
specificationschapter.
Unloaded or lightly loaded vehicles
The braking system has been designed to safely stop your vehicle when
fully loaded to its GVWR.
When operating empty or lightly loaded, sudden or hard braking
may induce wheel lockup with loss of vehicle control and the
possibility of accident and serious injury, especially on wet or slippery
road surfaces.
TRAILER TOWING
Towing a trailer places an additional load on your vehicle’s engine,
transmission, axle, brakes, tires and suspension. Inspect these
components carefully prior to and after any towing operation.
Your vehicle’s load capacity is designated by weight, not by volume, so
you cannot necessarily use all available space when loading a vehicle.
2nd unit bodies are not included in maximum trailer weight ratings. The
weight of the additional“body”must be subtracted from the maximum
trailer weight.
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Trailer brakes
Electric brakes and manual, automatic or surge-type trailer brakes are
safe if installed properly and adjusted to the manufacturer’s
specifications. The trailer brakes must meet local and Federal
regulations.
Do not connect a trailer’s hydraulic brake system directly to your
vehicle’s brake system. Your vehicle may not have enough
braking power and your chances of having a collision greatly increase.
Trailer lamps
Trailer lamps are required on most towed vehicles. Your vehicle may be
equipped with one of two possible trailer wiring designs. Make sure all
running lights, brake lights, turn signals and hazard lights are working.
See your dealer or trailer rental agency for proper instructions and
equipment for hooking up trailer lamps.
Driving while you tow
When towing a trailer:
•Turn off the speed control. The speed control may shut off
automatically when you are towing on long, steep grades.
•Consult your local motor vehicle speed regulations for towing a trailer.
•To eliminate excessive transmission shifting, use a lower gear. This will
also assist in transmission cooling.
•Anticipate stops and brake gradually.
•Do not exceed the GCWR rating or transmission damage may occur.
Servicing after towing
If you tow a trailer for long distances, your vehicle will require more
frequent service intervals. Refer to your scheduled maintenance guide for
more information.
Trailer towing tips
•Practice turning, stopping and backing up before starting on a trip to
get the feel of the vehicle trailer combination. When turning, make
wider turns so the trailer wheels will clear curbs and other obstacles.
•Allow more distance for stopping with a trailer attached.
•The trailer tongue weight should be 10–15% of the loaded trailer
weight.
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