
Tractor-trailer connections
To reduce the risk of personal injury, use extreme caution when
making brake and light connections. Inclement weather and
accumulated road contamination deposits on handhold and stepping
surfaces require extra care to avoid slip and falls. Provide adequate
lighting of working areas.
Do not climb on the back of the tractor unless it has been
provided with a deck plate and handholds. Use a three-point
stance when climbing up and down from a deck plate. Do not jump
from the vehicle. Whenever possible, make all connections while
standing on the ground.
Connecting and disconnecting a trailer with air suspension
When connecting to a trailer:
•Press the lower portion of the switch and air will exhaust from the air
suspension system.
•After making the connection to the trailer, press the upper portion of
the switch, then raise the landing gear.
When disconnecting the trailer:
•Lower the landing gear, then press the lower portion of the switch.
•Disconnect the brake hoses, trailer-side and rear light connectors,
then pull the release lever on the fifth wheel.
The upper portion of the switch must be pressed before operating with a
trailer or operating in the bobtail mode.
Suspension conversions
It is not recommended, or approved, that suspension conversions be
performed. However, it is understood that, on occasion, aftermarket
add-on suspensions 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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•Never engage the clutch while coasting.Re-engaging the clutch
after coasting may not only cause a great shock to the clutch, but the
whole drivetrain. Internal engine damage and/or clutch and flywheel
failure can result from this.
If your vehicle’s transmission is equipped with a ceramic clutch, you
must start the vehicle moving in first gear and engage the clutch before
pressing the accelerator at idle. Also, don’t try to slip the clutch by
raising engine RPM and riding or feathering the clutch pedal since the
vehicle will experience erratic engagement. Erratic engagement can
cause the engine stalling and potential serious damage to the vehicle’s
driveline components.
Clutch brake (vehicles equipped with a non-synchronized
transmission) - Vehicle stationary
A clutch brake is used to stop the transmission input shaft rotation so
that the initial 1 (First) or R (Reverse) gear selection can be
accomplished when the vehicle is stationary and the engine is running at
idle speed. Clutch brake application occurs in the last inch (25 mm) of
clutch pedal travel.
When using the clutch brake, fully depress the clutch pedal and shift the
transmission into 1 (First) or R (Reverse). If the transmission won’t go
into one of these gears, slowly release the clutch pedal while applying
light pressure on the transmission shift lever until it shifts into gear.
Note:After engagement of 1 (First) gear,do notuse the clutch brake
for upshifting or downshifting. If you do, clutch brake life will shorten
and gear selection shift efforts may increase.
Double-clutch procedures - vehicles equipped with a
non-synchronized transmission
In order to properly upshift or downshift, perform the following steps:
1. Depress the clutch pedal to disengage the clutch.
2. Shift the transmission into neutral.
3. Release the clutch pedal.
If upshifting, wait until the engine speed matches the transmission
speed of the gear you are selecting.
If downshifting,accelerate the engine until the engine speed matches
the input speed of the gear you are selecting. Depress the clutch pedal
immediately and shift into the desired gear, then release the clutch
pedal.
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MANUAL TRANSMISSION OPERATION (IF EQUIPPED)
Note:Continued use of a damaged or worn clutch, prolonged clutch
slippage or downshifting at excessive speeds can result in a failure of the
engine, transmission or clutch components.
Note:To avoid premature clutch wear and failure, do not drive with
your foot resting on the clutch pedal or use it to hold the vehicle at a
standstill on an upgrade as when waiting for a traffic light.
Manual transmission shift patterns
are displayed on either the shift
lever knob or the sun visor.
Study this information carefully before you drive the vehicle even though
you may be familiar with similar units. Do not attempt to drive the
vehicle without knowing the exact shift pattern of the transmission.
Consult your authorized dealer if any questions exist as to the shifting
instructions posted in your vehicle.
Do not coast the vehicle with the clutch pedal depressed or with
the transmission in neutral. This practice could result in loss of
vehicle control.
Driving hints
The following driving hints are provided as a brief, general guide in
operating the different manual transmissions used in your vehicle.
•When shifting into 1 (First) or R (Reverse) with vehicle standing still,
quickly release and depress the clutch pedal (if necessary to complete
gear engagement).
•Always use the lowest (or most appropriate) gear to start the vehicle.
•Always use a gear ratio low enough to allow the engine to operate
above the minimum engine operation speed range.
•Do not lug the engine.
•Do not slam or jerk the gearshift lever into gear.
•When more power is required, shift to a lower gear and accelerate the
engine near the governed speed.
R 1 3 5
4
6 2
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Shifting with a synchronized transmission
With the clutch pedal depressed, use 2 (Second) gear synchronizer to
stop the clutch disc rotation; this allows smooth engagement of 1 (First)
or R (Reverse) To complete the gear engagement, it may be necessary to
apply light pressure to the gearshift lever during initial engagement of
the clutch. It takes a second or two to match gear speeds; steady
pressure on the gearshift lever will help the synchronizer perform its job
more quickly. If the gearshift lever is forced into position, this action
defeats the purpose of the synchronizer by causing gear clash.
Shifting with a non-synchronized transmission
Refer toClutch brakeandDouble clutch proceduresin theClutch
section of this chapter.
Operating the Eaton FS-5205A 5–speed transmission
The 5-speed transmission is
equipped with five forward gears
and one reverse. The 2nd, 3rd, 4th
and 5th gears are synchronized. The
shift pattern is embossed on the
gear shift knob.
Do not shift the transmission into R (Reverse) while the vehicle is
moving as this could damage the transmission.
To go forward
With the engine idling, depress the clutch pedal and shift into 1 (First).
Engage the clutch while pressing the accelerator to start forward.
Operate the clutch and upshift as required by driving conditions.
To go backward
Reverse is obtained by putting the gearshift lever in R (Reverse) and
engaging the clutch while pressing lightly on the accelerator.
R 2 4
3 5 1
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Operating the Eaton FS–5406A, FS–5406N, FS–6406A and
FSO–6406A 6-speed transmissions
These 6-speed transmissions are
equipped with six forward gears and
one reverse. All the forward gears
are synchronized. The shift pattern
is embossed on the gear shift knob.
Do not shift the transmission into 1 (First) or R (Reverse) while the
vehicle is moving as this could damage the transmission.
To go forward
With the engine idling, depress the clutch pedal and shift into 1 (First).
Engage the clutch while pressing the accelerator to start forward.
Operate the clutch and upshift as required by driving conditions.
To go backward
Reverse is obtained by putting the gearshift lever in R (Reverse) and
engaging the clutch while pressing lightly on the accelerator.
Operating the Spicer ES56-7B and ES066-7B 7-speed
transmissions
These 7-speed transmissions are
equipped with seven forward gears
and one reverse. The 2nd, 3rd, 4th,
5th, 6th and 7th gears are
synchronized. The shift pattern is
embossed on the gear shift knob.
Do not shift the transmission into 1 (First) or R (Reverse) while the
vehicle is moving as this could damage the transmission.
R 1 3 5
4
6 2
2 4 6
3 5 71 R
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To go forward
With the engine idling, depress the clutch pedal and shift into 1 (First).
Engage the clutch while pressing the accelerator to start forward.
Operate the clutch and upshift as required by driving conditions.
To go backward
Reverse is obtained by putting the gearshift lever in R (Reverse) and
engaging the clutch while pressing lightly on the accelerator.
POWER TAKE-OFF (PTO) OPERATION (IF EQUIPPED)
Vehicles equipped with an Allison automatic transmission
(except 3000 Series applications and vehicles equipped with a
Caterpillar engine)
The PTO 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), then engage the PTO.
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 into gear. The PTO should never
be engaged by clashing the gear teeth as 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
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, 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 injury and/or property damage.
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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.
When the differential is locked, the vehicle’s turning radius will increase
(vehicle will “under-steer”)
The differential can be locked or unlocked when the vehicle is moving at
a constant speed of less than 25 mph (40 km/h) and while the wheels
are not slipping. The differential must not be locked when the vehicle is
traveling down steep grades and traction is minimal.
Note:Never use the differential lock at vehicle speeds above 25 mph
(40 km/h).
Note:The driver-controlled differential lock function will vary with some
transmissions.
•Vehicles equipped with an Allison 3000 Series transmission:The
differential lock and differential lock light will automatically disengage
at speeds above 25 mph (40 km/h). The differential lock will remain
off until either the vehicle is restarted or the differential lock switch is
turned off then back on.
•Vehicles equipped with a 5–speed, 6–speed or 7–speed manual:
The differential lock and differential lock light will automatically
disengage at speeds above 25 mph (40 km/h). The differential lock
will remain off until either the vehicle is restarted or the differential
lock switch is turned off then back on.
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.
TWO-SPEED REAR AXLE (IF EQUIPPED)
A two-speed rear axle allows the driver to select a LO range for greater
pulling power and a HI range for greater road speed and fuel economy.
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These ranges can also be used to provide additional steps between
transmission shifts when driving on steep grades and/or fuel economy
may be factors.
Note:Do not shift between ranges when the speed control is on.
Never shift a two-speed axle when descending a steep grade as
this may cause loss of vehicle control and result in personal injury.
Axle shifting
Manual transmissions:
•To downshift,select the next lower gear, release and depress the
accelerator pedal rapidly, or while holding the accelerator pedal down,
release and engage the clutch rapidly.Note:The clutch method is
recommended when driving at slower speeds.
•To upshift,keep the accelerator pedal down, select the next higher
gear, release the accelerator and pause until the axle upshifts.Note:
De-clutch for smoother axle upshifts when driving at slower speeds.
Automatic transmissions:
•Use LO range for when you drive
a fully loaded vehicle on a severe
grade or in congested traffic. To
activate LO range, press the
upper portion of the switch.
•Use HI range for all normal
driving conditions with a lightly
loaded or partially loaded vehicle.
To activate HI range, press the
lower portion of the switch.
Note:You cannot split-shift with an automatic transmission. Also,
downshifting above 40 mph (64 km/h) may result in transmission or axle
damage.
Shifting the axle from LO to HI range - vehicle stopped
Place the transmission in N (Neutral), then press the lower part of the
switch.
Shifting the axle from LO to HI range - vehicle moving
Accelerate to approximately 35 mph (56 km/h), press the lower part of
the switch while the transmission is in N (Neutral), then release and
apply the accelerator.
LOW
2SPD
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