2008 FORD F750 brakes

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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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.
•If you are driving down a long or steep hill, shift to a lower gear. Do
not apply the brakes continuously, as they may overheat and become
less effective.
•The trailer tongue weight should be 10–15% of the loaded trailer
weight.
•If you will be towing a trailer frequently in hot weather, hilly
conditions, at GCW, or any combination of these factors, consider
refilling your rear axle with synthetic gear lube if not already so
equipped. Refer toLubricant specificationsin theMaintenance and
Specificationschapter for the lubricant specification. Remember that
regardless of the rear axle lube used, do not tow a trailer for the first
500 miles (800 km) of a new vehicle, and that the first 500 miles
(800 km) of towing be done at no faster than 70 mph (112 km/h) with
no full throttle starts.
•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 withoutaP[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.
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.
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Before hook-up, make sure:
•The fifth wheel jaws are fully opened.
•The fifth wheel is fully tilted back to prevent body damage when the
tractor is backed under a trailer.
•The trailer wheels are blocked and the trailer spring brakes are
adjusted and applied. Never chase a trailer.
•The brake hoses and light cords are clear of the fifth wheel.
Hook-up
1. 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.
2. Connect the service and emergency brake hoses and trailer light
connector. Refer toTractor-trailer connectionin theAir suspension
section of this chapter, adhering to the warning and using the three-point
stance while connecting and disconnecting the trailer.
3. 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.
4. Be sure the coupler release lever is in the locked position.
5. 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.
6. 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.
7. 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.
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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.
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Passenger compartment fuse panel
Fuse/Relay
LocationFuse Amp
RatingFuse Description
1 20A Horn relay
2 15A Flasher
3 20A Cigar lighter
4 10A Diagnostics, Parking brake warning
5 15A Blend door actuator, Climate mode, Back-up
lamps, DRL signal, Heated seats, Trailer ABS,
Exhaust brakes
6 — Not used
7 — Not used
8 5A Radio, GEM 4
9 5A Power window switch LED and relay
10 15A Heated mirrors
11 5A Wiper motor, Washer pump relays
12 10A Stoplamp switch (Hydraulic brake vehicles
only), Allison push-button shifter
13 20A Cluster, Radio
14 10A Interior lamp relay
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4. Remove the jumper cable from the positive (+) terminal of the
disabled vehicle’s battery.
After the disabled vehicle has been started and the jumper cables
removed, allow it to idle for several minutes so the engine computer can
relearnits idle conditions.
WRECKER TOWING INSTRUCTIONS
Before moving the towed vehicle, check for adequate road clearance of
vehicle components. It is recommended the towed vehicle be unloaded
prior to being towed to reduce any abnormal load to the vehicle
components resulting from the towing procedures. Before towing, be
sure to fully release the parking brake. The spring-actuated type parking
brake can be reset by recharging the air system with at least 64 psi
(441 kPa) of air. If the brake system will not retain air pressure, then the
spring brakes must be released manually. Refer toParking brakein the
Drivingchapter
Note:For towing, make sure the vehicle is securely connected to the
tow vehicle and the tow vehicle parking brakes are applied before
releasing the disabled vehicle’s spring brakes.
To reduce the risk of personal injury or property damage when
manually releasing the spring brakes, be sure to block the wheels
so the vehicle cannot move once the brakes are released.
Towing the vehicle with the front wheels suspended
When it is necessary to tow a vehicle with the front wheels suspended,
extra precautions must be taken to avoid transmission or differential
damage. Proceed as follows:
•Remove the axle shafts from the axle assembly to prevent the wheels
from driving the differential and the transmission.
•The wheel hub ends must be covered to prevent loss of axle lubricant
and entrance of other contaminants. If the axle shafts are not
removed, removal of the driveshaft is required.
+–+–
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Supplement
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Roadside Emergencies
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GENERAL SERVICING GUIDELINES AND PRECAUTIONS
As with any machine, care should be taken to avoid being injured when
performing maintenance, repairs or system checks. Improper or
incomplete service could result in the vehicle not working properly
which, in turn, may result in personal injury or damage to the vehicle or
equipment. It is the operator’s responsibility to see that the vehicle
receives proper care and maintenance. If you have any questions about
performing some service, have the service done by a qualified technician.
Servicing guidelines
When servicing your vehicle, always:
•turn off the ignition unless the particular procedure calls for the
engine to be running.
•set the parking brake or chock the wheels.
•use support stands, not a jack, whenever you must be under a raised
vehicle.
•do not smoke.
•wear safety glasses for eye protection.
•operate the engine in a well-ventilated area
•do not work on the brakes or the clutch unless the proper precautions
are taken to avoid inhaling friction material dust.
•do not wear loose-fitting clothing, hanging jewelry, watches or rings.
•avoid contact with hot metal parts. Allow the hot components to cool
before working with, or around them.
Quality service parts are available through your dealer. If dealer parts are
not used, the owner must make sure that the parts that are being used
are equivalent quality to dealer parts.
The use of inferior parts can adversely affect the quality and
reliability of your vehicle which, in turn, can result in property
damage, personal injury or death.
Note:To avoid damage to the vehicle’s electrical components, disconnect
the positive (+) and negative (-) battery cables prior to electric welding.
Attach the welder ground cable as close as possible to the part being
welded. If it is necessary to weld close to an electrical component, it is
recommended that the electronic component be temporarily removed.
Follow the periodic lubrication procedures and regular inspection
intervals as outlined. Have your dealer or service center inspect your
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non-asbestos, fiberglass, mineral wool, aramid or carbon) may be a
potentially serious health hazard.
Note:Persons handling brake linings should follow all precautions listed
below:
1. Always wear a respirator approved by the National Institute of
Occupational Studies of Health (NIOSH) or Mine Safety and Appliance
(MSA) during all brake service procedures. Wear the respirator from
removal of the wheels through assembly.
2.Neveruse compressed air or dry brushing to clean brake parts or
assemblies.
3. Clean brake parts and assemblies in open air. During assembly,
carefully place all parts on the floor to avoid getting dust in the air. Use
an industrial vacuum cleaner with a HEPA filter system to clean dust
from the brake drums, backing plates and other brake parts. After using
the vacuum, remove any remaining dust with a rag soaked in water and
wrung until nearly dry.
4.Neveruse compressed air or dry sweeping to clean the work area.
Use an industrial vacuum cleaner with a HEPA filter system and rags
soaked in water until wrung until nearly dry. Dispose of used rags with
care to avoid getting dust in the air. Use an approved respirator when
emptying vacuum cleaners and handling used rags.
5.Worker clean-up:Wash your hands before eating, drinking or
smoking. Vacuum your work clothes after use and then launder them
separately, without shaking them, to prevent fiber dust getting into the
air.
Air brakes - inspection and adjustment
A regular schedule for periodic cleaning, lubrication and adjustment
inspection should be established based on the type of vehicle operation.
It is difficult to predetermine an exact maintenance interval (time or
mileage), since vehicles will be used in a wide variety of applications and
conditions. If you are uncertain of the proper schedule and procedures
for your vehicle, contact your dealer.
Periodic checking of push rod travel or brake adjustment is essential for
effective braking. Push rod travel should be checked every service
interval to determine if adjustment is correct. Brake chamber push rods
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Maintenance and Specifications
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