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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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.
Vehicles equipped with an Allison 3000 Series automatic
transmission
The PTO drive gear is engine driven and provides direct engine power.
The PTO can be operated when the vehicle is either stationary or
moving.
The PTO gear is in constant mesh with the drive gear in the torque
converter housing. A friction clutch or constant drive is used to transmit
power to the PTO.
Vehicles equipped with a Caterpillar engine
The PTO will only operate if the transmission is in N (Neutral). This
feature can be overridden by a special service tool; see your dealer or
service representative for more information.
Vehicles equipped with a manual transmission
Transmission-mounted PTO units are available for local installation on
your vehicle. See yourBody Builder’s Layout Bookfor restrictions on
use and installation of PTO units.
To engage the PTO unit, stop the vehicle and place the transmission in N
(Neutral). Depress the clutch and allow the gears to stop rotating, then
engage the PTO unit. The PTO can also be selected with the
transmission in gear as long as the clutch is depressed.
When operating the PTO with the vehicle stationary, first set the parking
brake (chock the wheels if the vehicle is on a hill or another uneven
surface).
REAR AXLE INFORMATION
Axle operating temperature normally will not exceed 100°F (38°C). If
the operating temperature exceeds 230°F (110°C), the rate of axle
lubrication oxidation will increase and shorten the life of the lubricant
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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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Shifting the axle from HI to LO range - vehicle stopped
Place the transmission in N (Neutral), then press the upper part of the
switch.
Note:Do not shift the axle to LO range with the vehicle in motion.
Split-shifting (combined axle and transmission shift - manual
transmissions only)
Split-shift sequence
Ratio
combination1234567891011
Transmission
gear1st 1st 2nd 2nd 3rd 3rd 4th 4th 5th 6th 6th
Axle range LO HI LO HI LO HI LO HI LO LO HI
To downshiftthe axle to a slower ratio and shift the transmission, shift
the transmission and move the control switch to the lower ratio before
the clutch is re-engaged.
To upshiftthe axle and shift the transmission, move the control switch
to a faster ratio and make the transmission shift in the usual manner.
Ratio extender use
Low End
A two-speed axle can be used as a ratio-extender when split shifting is
not necessary. For low end use, just shift the axle into LO to start out,
and shift to HI when the extra torque is no longer needed.
Transmission (5-speed) 1st 1st 2nd 3rd 4th 5th 6th
Two-speed axle Axle low Axle high
High End
To use the two-speed axle as a high end ratio-extender, stay in the LO
range for normal upshifts and only shift the axle to HI on the freeway for
greater road speed.
Transmission
(5-speed)1st 2nd 3rd 4th 5th 6th
Speed
Two-speed axle Low for gradeability Axle high
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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.
Note:Do not exceed the GVWR or the GAWR specified on the
certification label.
Towing trailers beyond the maximum recommended gross trailer
weight exceeds the limit of the vehicle and could result in
engine damage, transmission damage, structural damage, loss of vehicle
control, vehicle rollover and personal injury.
Model Maximum
GVWR - lb.
(kg)Maximum
GCWR - lb.
(kg)*
F-650 Regular/Super/Crew Cab 26000 (11793) 40000 (18143)
F-750 Regular/Super/Crew Cab 30000 (13608) 45000 (20412)
F-750 Regular/Super/Crew Cab 33000 (14969) 60000 (27216)
* Figures shown are the maximum available for each model. Actual
ratings may be less, depending on your transmission. Check with your
sales consultant for the exact rating on your vehicle.
Preparing to tow
Use the proper equipment for towing a trailer and make sure it is
properly attached to your vehicle. See your dealer or a reliable trailer
dealer if you require assistance.
Hitches
Do not use hitches that clamp onto the vehicle’s bumper or attach to the
axle. You must distribute the load in your trailer so that 10–15% of the
total weight of the trailer is on the tongue.
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Safety chains
Always connect the trailer’s safety chains to the frame or hook retainers
of the vehicle hitch. To connect the trailer’s safety chains, cross the
chains under the trailer tongue and allow slack for turning corners.
If you use a rental trailer, follow the instructions that the rental agency
gives to you.
Do not attach safety chains to the bumper.
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:
•Keep your speed no faster than 70 mph (112 km/h) during the first
500 miles (800 km) of towing a trailer, and don’t make full throttle
starts.
•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 yourScheduled Maintenance Guide
for more information.
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