2008 FORD F650 trailer

System park
With both knobs pushed in (normal driving position), the parking brakes
for both the tractor and trailer can be applied by pulling the parking
brake knob (2) out, exhausting air from the tractor spring brakes,
simultaneously causing the trailer air supply valve to pop out, applying
the trailer brakes.
Trailer charge
If both knobs are out, and you want to recharge the trailer while leaving
the tractor spring brakes applied, the trailer air supply (1) can be
pushed in to recharge the trailer air supply line. This mode may also be
used to park a combination vehicle with tractor spring brakes.
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Supplement
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Driving
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Automatic application
If both knobs are pushed in and the brake system air pressure is reduced
to approximately 35 psi (249 kPa), the trailer air supply (1) knob will
automatically pop out applying the emergency or parking brakes on the
trailer. If the trailer air supply (1) knob is manually held in and the air
pressure is reduced to approximately 30 psi (207 kPa), a tripper piston
within the valve will move, exhausting the trailer air supply, applying the
trailer brakes. Further reduction of air pressure, while holding the trailer
air supply knob in, will cause the parking brake knob to pop out at 25 psi
(172 kPa).
Actuation of trailer park (emergency) or tractor bobtail position
To actuate the trailer brakes only, pull out the trailer air supply knob (1).
The trailer brakes are now applied whether emergency or spring brakes
are used on the trailer.
This mode is also used when the tractor or truck with trailer is used
during bobtail operation.
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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).
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.
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Supplement
USA(fus)
Driving
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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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Supplement
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Driving
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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.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
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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.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
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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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