lowering the frame for loading. Pressing the lower portion of the switch
causes air to fill the air springs so the vehicle will remain normal ride
height.
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).
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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 250°F (120°C). The converter temperature should not exceed
300°F (144°C).
Power take-off (PTO) operation with an Allison automatic
transmission (except MD applications and vehicles equipped with
a Caterpillar 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.
If engagement is prevented by the gear teeth not meshing properly,
release the brakes and allow the vehicle to creep slightly - or shift the
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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 25 mm (one inch)
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’tgo
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 in to 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.
MANUAL TRANSMISSION OPERATION (IF EQUIPPED)
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.
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.
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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.
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. When
more power is required, shift to a lower gear and accelerate the engine
near the governed speed.
Driving hints
The following driving hints are provided as a brief, general guide in
operating the different manual transmissions used in your vehicle.
•Always use the lowest gear to start the vehicle.
•Do not slam or jerk the gearshift lever into gear.
•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).
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.
R 1 3 5
4
6 2
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Shifting with a non-synchronized transmission
Refer toClutch brakeandDouble clutch proceduresin theClutch
section of this chapter.
Operating the Eaton FS-4205A and FS-5205A 5–speed
transmissions
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.
Operating the Eaton FS–5406A, FS–5406N, FS–6406A and
FS–6406N 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.
R 2 4
3 5 1
R 1 3 5
4
6 2
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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.
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 Eaton 8908LL 10-speed transmission
These transmissions have five
forward speeds in the LO range, and
four forward speeds in the HI range.
These transmissions employ a Deep
Reduction Valve and control to allow
for a LO-LO gear operation for
adverse conditions. Study the
instruction plate on the sun visor
thoroughly and learn the shift
pattern of your transmission.
2 4 6
3 5 71 R
27
3
6
2 LO
LO-LO
8
4
R R
R R
5 1
1
Neutral
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