
The ABS operates by detecting the
onset of wheel lockup during brake
applications and compensating for
this tendency. The wheels are
prevented from locking even when
the brakes are firmly applied. The
accompanying illustration depicts
the advantage of an ABS equipped
vehicle (on bottom) to a non-ABS
equipped vehicle (on top) during hard braking with loss of front braking
traction.
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 Anti-Lock system 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.
Driving
115

Do not drive or continue to drive if the low air pressure buzzer
is sounding or the brake warning light is lit. These warnings
indicate that air pressure is not to normal operating level. Continued
use of the vehicle could result in loss of braking ability.
Avoid repeated light application of the brake pedal. This will
deplete air pressure faster and could result in loss of braking
capability.
Periodically check the air pressure
gauge while driving. Pressure should
range between approximately 724 to
930 kPa (105-135 psi). The air
compressor governor cut-in and
cut-out pressure settings are preset
at the factory and are not
adjustable.
When air pressure is insufficient
(below 414 kPa [60 psi]), a warning
light illuminates and a buzzer
sounds when the ignition is in the
ON position.
This condition may be caused by excessive brake applications depleting
the system air pressure. If this condition occurs, stop driving the vehicle
until the compressor has fully recharged the air system. Do not move the
vehicle in this condition because the brake system may be inoperative.
Select a gear ratio to help slow your vehicle before descending grades.
Supplement with brakes as required to safely slow the vehicle and avoid
overspeeding the engine.
Air chamber stroke indication
All Ford air chamber push rods have orange stroke indicator stripes that
alert the operator when the braking system requires adjustment or
repair. The orange stripe is painted on the air chamber push rod at the
slack adjuster readjustment stroke dimension.
Air brake inspection and adjustment should be performed by a qualified
service technician in accordance with the instructions in the Ford Truck
Service Manual.
0 30 12090 60
150AIR
PRESSUREPSI
Driving
120

Exhaust brake operating characteristics
When you remove your feet from both the accelerator and clutch pedals
and the exhaust brake switch is in the ON position, the exhaust brake is
activated. The following conditions should exist if the brake is operating
properly:
•A slight change in the sound of the engine when the exhaust brake is
activated.
•Exhaust smoke appears normal.
•Engine temperature remains in the normal operating range.
•Road speed usually decreases when the exhaust brake is applied
during a descent, except when the vehicle is carrying a heavy load or
the grade is extremely steep. In these instances, you may need to
apply the service brakes occasionally.
•During a descent, the tachometer usually shows a drop in RPM
depending on the grade and the vehicle load.
•Do not expect a retarding effect similar to sudden hard application of
the service brakes. The exhaust brake retards the vehicle with a
smooth braking effect.
•Depending on the grade and vehicle load, you may or may not feel the
retarding force acting against your body when the brake is applied.
The brake’s retarding force is actually preventing the vehicle from
going much faster.
Make sure the exhaust brake is turned off before shutting off the engine.
Installing an exhaust or auxiliary brake should never allow the
engine to exceed maximum governed speeds under any
conditions.
Air brake reservoir draining
Failure to drain air brake reservoirs can result in a reduction or
loss of braking ability due to fluid accumulation in the reservoir
and/or possible freeze-up during cold weather.
Driving
129

The N (Neutral) position may also be used during stationary operation of
the Power Take-Off (PTO), if equipped.
Do not allow your vehicle to coast in N (Neutral). Engine
braking is not available in N (Neutral). Allowing your vehicle to
coast in N (Neutral) may result in loss of vehicle control and severe
internal transmission damage.
D (Drive—Normal driving position)
In this position, the transmission starts in first gear and automatically
shifts through second, third, fourth and fifth depending on load and
speed demands. When the vehicle is slowing down, the transmission will
automatically downshift. This range is used for highway driving under
normal conditions.
4 and 2 (Fourth and Second)
Use this position when road, load or traffic conditions make it desirable
to restrict the automatic shifting to a lower range. These ranges provide
greater engine braking than D (Drive). When conditions no longer
require these lower gears, shift back to D (Drive).
1 (First)
The transmission has to be manually shifted into 1 (First) and will not
shift into a higher gear. Use this position when pulling through mud or
snow, driving up steep grades, hauling extra heavy loads or where
maximum reduction is required.
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.
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.
Driving
139

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 the 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
LowAxle 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
Axle
High Two-Speed Axle Low for Gradeability
DRIVING THROUGH WATER
Do not drive quickly through standing water, especially if the depth is
unknown. Traction or brake capability may be limited and if the ignition
system gets wet, your engine may stall. Water may also enter your
engine’s air intake and severely damage your engine.
If driving through deep or standing water is unavoidable, proceed very
slowly. Never drive through water that is higher than the bottom of the
hubs (for trucks) or the bottom of the wheel rims (for cars).
Once through the water, always try the brakes. Wet brakes do not stop
the vehicle as effectively as dry brakes. Drying can be improved by
moving your vehicle slowly while applying light pressure on the brake
pedal.
Driving through deep water where the transmission vent tube is
submerged may allow water into the transmission and cause
internal transmission damage. Have the fluid checked and, if
water is found, replace the fluid.
Driving
148

The fuses are coded as follows:
Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse
Panel Description
1 20A Horn
2 15A Turn/Hazard lamps
3 20A Cigar lighter
4 10A Diagnostic connectors
5 15A Back-up lamps, Daytime Running
Lamps (DRL) relays, Blend door
actuator, Heated seat module
(SuperCrewzer only), On/Off fan
clutch (SuperCrewzer only),
Warning chime module
(SuperCrewzer and Ambulance)
6—Not used
7—Not used
8 5A Radio, GEM
9 5A Switch Illumination (headlamp,
power windows, power door
locks), Power window relay,
Trailer hook-up lamps
(SuperCrewzer only)
10—Not used
11 30A Wiper motor, Washer pump relay
12 10A Stoplamp switch (hydraulic brake
vehicles only)
13 20A Radio, Cluster, 7.3L Power Stroke
Powertrain Control Module
(PCM), Keep Alive Memory
14 10A Interior lamps, Running board
lamps (SuperCrewzer only)
Roadside Emergencies
153

Connecting the jumper cables
1. Position the vehicles so that they
do not touch one another.
2. Apply the parking brakes.
3. Switch off the engine and any
unnecessary electrical equipment.
4. Find the positive (+) terminal of
the discharged battery.
5. Using the jumper cables, connect
the positive (+) terminal of the
discharged battery to the positive
(+) terminal of the booster battery.
NOTE:In the illustration,
lightning bolts are used to
designate the assisting (boosting)
battery.
6. Connect one end of the cable to
the negative (-) terminal of the
booster battery and the other end to
a ground at least 12 inches from the
battery of the discharged vehicle. The vehicle frame is usually a good
ground.
7. Ensure that the jump leads are clear of moving parts of the engine,
and that the clamps from one cable do not touch the clamps on the
other cable.
8. Do not lean over the batteries when making the connections.
Do not connect the end of the second cable to the negative (-)
terminal of the battery to be jumped. A spark may cause an
explosion of the gases that surround the battery.
Jump starting
1. Start the booster vehicle and run the engine at moderately increased
speed.
2. After a few minutes, start the engine of the vehicle with the
discharged battery.
3. After starting, run the engine at about 1,000 RPM for 3–5 minutes.
13
2
4
Roadside Emergencies
163

Tires are one of the weaker weight carrying components of the
vehicle. Do not overload the vehicle beyond safe load carrying
capacity.
Avoid hammering rim with steel hammers.
Never run the engine with one wheel off the ground.
Failure to retighten wheel lug nuts as required could allow the
wheel to come off while the vehicle is in motion, possibly causing
loss of vehicle control and collision. Loose wheel studs may also cause
shimmy and vibration.
Use of aftermarket wheel assemblies is not recommended; they
may be incompatible with your vehicle and may result in
equipment failure and possible injury. Replacement with used wheels is
not advised; they may have been treated harshly or have high mileage
and could fail without warning.
A wheel or tire of the wrong size or type may adversely affect
such things as load carrying capacity, wheel and bearing life,
brake cooling, speedometer/odometer calibration, stopping ability,
headlight aim, bumper height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
Maintenance and Specifications
211