
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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124

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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125

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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126

To go forward
With the engine idling, depress the clutch pedal and move the gearshift
lever to the neutral position.
Place the range selector in the LO
range and the Deep Reduction
Button in the OUT/REARWARD
position or,
place the Deep Reduction in the
IN/FORWARD position if you want
to start in LO-LO under adverse
conditions.
To start forward, place the gearshift lever in LO gear and disengage the
clutch while slightly depressing the accelerator. Operate the clutch and
upshift through the shift pattern (up to 4th) as required by driving
conditions. To shift into the HI range from 4th gear (LO range), place
the range control button in the HI range, then shift to 5th gear. Upshift
through 8th. When downshifting, shift 8-7-6-5, depress the range control
button to LO, then move the gearshift lever to 4-3-2-1-LO as necessary.
Never move the gearshift lever to the LO position when the transmission
is in the HI range.
Use LO-LO only for adverse conditions by changing the Deep Reduction
Button to the IN/FORWARD position, while the range selector is in the
LO range and the gearshift lever is in the LO position. Do not pre-select
Deep Reduction.
5
17
3
6
2 LO
LO-LO
8
4
R R
R
Neutral
5
17
3
6
2 LO
LO-LO
8
4
R R
R
Neutral
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127

To go forward
With the engine idling, depress the
clutch pedal and push the range
control button to the LO range
position. Shift into the LO gear
position and engage the clutch while
pressing on the accelerator to start
forward. Operate the clutch and
upshift through the pattern as
required by driving conditions. To
shift into the HI range from 5th gear
(LO range), place the range control
in the HI range position, then shift into 6th gear. When downshifting
from HI to LO, place the range control into the LO range, then downshift
from 6th gear to 5th gear (below 1,500 engine RPM).
To go backward
Reverse is obtained by putting the
gearshift lever in R (Reverse) and
the range control button in LO or
HI.
Power-take off operation (PTO) with a manual transmission
Transmission-mounted power take-off units are available for local
installation on your vehicle. See your Body Builder’s Layout Book for
restrictions on use and installation of power take-off units.
To engage the PTO unit, stop the vehicle and place the transmission
control in 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 unit with the vehicle stationary, first set the
parking brake (chock the wheels if the vehicle is on a hill or other
unlevel surface).
7
29
4
8
3 6
1
10
5
R
Neutral
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129

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
and seals, requiring axle lubrication changes to become more frequent to
preserve the axle. Extreme Pressure (EP) lubricants should not be run
consistently above 230°F (110°C).
Gross axle weight
Your truck has gross axle weight, gross vehicle weight and gross
combination weight ratings. Do not exceed these ratings.
Exceeding these ratings by overloading can cause component
failure resulting in property damage, personal injury or death.
Rear axles with locking or limited-slip differentials
If your vehicle is equipped with a locking or limited-slip differential, note
the following:
•Power will be transmitted to the opposite wheel should one of the
wheels begin to slip.
•Both wheels must be raised free of the ground should it be necessary
to operate one wheel with the vehicle stationary.
If both wheels are not raised free of the ground, the one wheel
that is not raised may pull the vehicle off its support, possibly
resulting in personal injury
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.
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130

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 - lbs.
(kg)Maximum
GCWR - lbs.
(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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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.
•After you have traveled 50 miles (80 km), thoroughly check your
hitch, electrical connections and trailer wheel lug nuts.
•To aid in engine/transmission cooling and A/C efficiency during hot
weather while stopped in traffic, place the gearshift lever in P (Park)
(if available on your automatic transmission) or N (Neutral) (manual
transmissions and automatic transmissions without a P [Park]
position).
•Vehicles with trailers should not be parked on a grade. If you must
park on a grade, place wheel chocks under the trailer’s wheels.
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