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F-550 SuperCab Chassis Cab Dual Rear Wheel
(Fifth Wheel Towing)
Engine Rear axle
ratioMaximum GCWR -
kg (lbs.)Maximum
trailer weight -
kg (lbs.)
6.8L 5.38 11793 (26000) 8255 (18200)
4x4 with automatictransmission
6.8L 4.88 10886 (24000) 7121 (15700)
6.8L 5.38 11793 (26000) 8029 (17700)
F-550 Crew Cab Chassis Cab Dual Rear Wheel
(Fifth Wheel Towing)
Engine Rear axle
ratioMaximum GCWR -
kg (lbs.)Maximum
trailer weight -
kg (lbs.)
4x2 with automatictransmission
6.8L 4.88 10886 (24000) 7212 (15900)
6.8L 5.38 11793 (26000) 8119 (17900)
4x4 with automatictransmission
6.8L 4.88 10886 (24000) 7076 (15600)
6.8L 5.38 11793 (26000) 7983 (17600)
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.
Load equalizing hitch
When hooking up a trailer using a load equalizing hitch, always use the
following procedure:
1. Park the unloaded vehicle on a level surface. With the ignition on and
all doors closed, allow the vehicle to stand for several minutes so that it
can level.
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2. Measure the height of a reference point on the front and rear bumpers
at the center of the vehicle.
3. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within 0–13 mm (0.5 in) of the reference
point. After proper adjustment, the rear bumper should be no higher
than in Step 2.
Note:Adjusting an equalizing hitch so the rear bumper of the vehicle is
higher than it was unloaded will defeat the function of the load
equalizing hitch and maycause unpredictable handling.
Safety chains
Always connect the trailer’s safety chains to the frame or hook retainers
of the vehicle hitch. To connect the trailer’s safetychains, 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 properlyand 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.
The braking system of the tow vehicle is rated for operation at the
GVWR not GCWR.
Trailer lamps
Trailer lamps are required on most towed vehicles. Make sure your
trailer lamps conform to local and Federal regulations. See your dealer or
trailer rental agencyfor proper instructions and equipment for hooking
up trailer lamps.
Using a step bumper (if equipped)
The rear bumper is equipped with an integral hitch and onlyrequires a
ball with a 25.4 mm (one inch) shank diameter. The bumper has a 2,270
kg (5,000 lb.) trailer weight and 227 kg (500 lb.) tongue weight capacity.
If it is necessaryto relocate the trailer hitch ball position, a
frame-mounted trailer hitch must be installed.
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Driving while you tow
When towing a trailer:
•Turn off the speed control. The speed control mayshut off
automaticallywhen you are towing on long, steep grades.
•Consult your local motor vehicle speed regulations for towing a trailer.
•To eliminate excessive shifting, use a lower gear. This will also assist
in transmission cooling. (For additional information, refer to the
Understanding the positions of the 4–speed automatic
transmissionsection in this chapter.
•Anticipate stops and brake gradually.
•Do not exceed the GCWR rating or transmission damage mayoccur.
Servicing after towing
If you tow a trailer for long distances, your vehicle will require more
frequent service intervals. Refer to your scheduled maintenance guide for
more information.
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 80 km (50 miles), thoroughly check your
hitch, electrical connections and trailer wheel lug nuts.
•To aid in engine/transmission cooling and A/C efficiencyduring hot
weather while stopped in traffic, place the gearshift lever in P (Park)
(automatic transmission) or N (Neutral) (manual transmissions).
•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.
Launching or retrieving a boat
When backing down a ramp during boat launching or retrieval,
•Do not allow the static water level to rise above the bottom edge of
the rear bumper.
•Do not allow waves to break higher than 15 cm (6 inches) above the
bottom edge of the rear bumper.
•Disconnect the trailer tow electrical connector to prevent blown fuses
caused bywater entering into your trailer’s electrical wiring.
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To remove a fuse use the fuse puller
tool provided on the fuse panel
cover.
The fuses are coded as follows.
Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
1 15A* Adjustable pedals
2 20A* Not used
3 20A* Not used
4 20A* Power point - instrument panel
5 20A* Not used
6 20A* Trailer tow turn/stop relay
7 30A* High beam headlamps/Flash to pass
8 — Not used
9 20A* Not used
10 10A* A/C clutch
11 20A* Radio (main)
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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
12 20A* Cigar lighter/OBD II
13 5A* Power mirrors/switches
14 15A* Daytime running lamps (DRL)
15 10A* Not used
16 15A* Not used
17 15A* Exterior lamps
18 20A* Turn lamps/Brake on-off switch (high)
19 10A* Bodysecuritymodule/4x4 module
20 — Not used
21 25A* Not used
22 20A* Engine control
23 20A* Engine control (gasoline engine only)
24 15A* Not used
25 10A* 4-Wheel Anti-lock Brake System (4WABS)
module
26 10A* Air bags
27 15A* Ignition switch Run feed
28 10A* EATC module/Front blower relaycoil
29 10A* Customer access
30 15A* Highbeam headlamps
31 15A* Clutch interlock switch (manual transmissions
only), Transmission range sensor (automatic
transmissions only) then to starter relay coil
(all transmissions)
32 5A* Radio (start)
33 15A* Front wiper
34 10A* Brake on-off switch
35 10A* Instrument cluster
36 10A* PCM Keep-Alive
37 15A* Horn
38 20A* Trailer tow park lamps and backup lamps
39 — Not used
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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
40 20A* Fuel pump
41 10A* Instrument cluster
42 15A* Delayed accessory
43 10A* Fog lamps
44 10A* Not used
45 10A* Ignition switch Run/Start feed
46 10A* Left-hand lowbeam
47 10A* Right-hand lowbeam
48 10A* Not used
101 30A** Trailer tow electric brake
102 30A** Door locks/Bodysecuritymodule
103 50A** Ignition switch
104 40A** Not used
105 30A** Injector driver module (Diesel engine only)
106 30A** Front wiper main
107 40A** Front blower motor
108 40A** Not used
109 30A** Heated seats
110 50A** Ignition switch
111 30A** 4WD/Shift on the fly
112 30A** Left-hand power seats
113 30A** Starter motor
114 30A** Right-hand power seats
115 20A** Trailer tow batterycharge
116 30A** Ignition switch
601 30A CB*** Door window motors
602 60A** 4WABS module
210 — Not used
211 — Not used
212 — Not used
301 — Front blower motor relay
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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
302 — Powertrain (EEC) relay
303 — Injector driver module relay(Diesel engine
only)
304 — Not used
305 — Trailer tow batterycharge relay
306 — Delayed accessory relay
307 — Starter relay
* Mini Fuses ** Maxi Fuses ***Circuit Breaker
CHANGING A FLAT TIRE
If you get a flat tire while driving:
•do not brake heavily.
•graduallydecrease the vehicle’s speed.
•hold the steering wheel firmly.
•slowlymove to a safe place on the side of the road.
The use of tire sealants is not recommended and may
compromise the integrityof your tires. The use of tire sealants
may also affect your tire pressure monitoring system (if equipped).
Spare tire information
Your vehicle maybe equipped with a spare tire that can be used as
either a spare or a regular tire. The spare tire is not equipped with wheel
trim. The wheel trim from the original wheel/tire maybe used on the
spare.
If your vehicle is equipped with 4WD, a spare tire of a different
size than the road tires should not be used. Use of such a tire
could result in damage to driveline components and an increased risk
of loss of vehicle control, vehicle rollover, personal injuryor death.
If your vehicle is equipped with a tire pressure monitoring
system, refer to Tire Pressure Monitoring System (if equipped)
in the Maintenance and specifications section for important information
before changing your tires. If the tire pressure monitoring system
becomes damaged, it will no longer function.
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•Revving the engine before turning it off mayreduce fuel economy.
•Using the air conditioner or defroster mayreduce fuel economy.
•You maywant to turn off the speed control in hillyterrain if
unnecessaryshifting between third and fourth gear occurs.
Unnecessaryshifting of this type could result in reduced fuel
economy.
•Warming up a vehicle on cold mornings is not required and may
reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
•Combine errands and minimize stop-and-go driving.
Maintenance
•Keep tires properlyinflated and use onlyrecommended size.
•Operating a vehicle with the wheels out of alignment will reduce fuel
economy.
•Use recommended engine oil. Refer toLubricant specificationsin
this chapter.
•Perform all regularlyscheduled maintenance items. Follow the
recommended maintenance schedule and owner maintenance checks
found in your vehicle scheduled maintenance guide.
Conditions
•Heavilyloading a vehicle or towing a trailer mayreduce fuel economy
at anyspeed.
•Carrying unnecessaryweight mayreduce fuel economy(approximately
0.4 km/L [1 mpg] is lost for every180 kg [400 lb] of weight carried).
•Adding certain accessories to your vehicle (for example bug
deflectors, rollbars/light bars, running boards, ski/luggage racks) may
reduce fuel economy.
•Using fuel blended with alcohol maylower fuel economy.
•Fuel economymaydecrease with lower temperatures during the first
12–16 km (8–10 miles) of driving.
•Driving on flat terrain offers improved fuel economyas compared to
driving on hillyterrain.
•Transmissions give their best fuel economywhen operated in the top
cruise gear and with steadypressure on the gas pedal.
Maintenance and Specifications
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