tow FORD SUPER DUTY 2008 2.G Owner's Guide

GAWR (Gross Axle Weight Rating)– is the maximum allowable
weight that can be carried by a single axle (front or rear).These
numbers are shown on the Safety Compliance Certification Label
located on the B-Pillar or the edge of the driver’s door. The total
load on each axle must never exceed its GAWR.
Exceeding the Safety Compliance Certification Label axle weight
rating limits could result in substandard vehicle handling or
performance, engine, transmission and/or structural damage, serious
damage to the vehicle, loss of control and personal injury.
Note:For trailer towing information refer toTrailer towingfound in
this chapter or theRV and Trailer Towing Guideprovided by your
authorized dealer.
GVW (Gross Vehicle Weight)– is the Vehicle Curb Weight + cargo +
passengers.
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GVWR (Gross Vehicle Weight
Rating)– is the maximum
allowable weight of the fully loaded
vehicle (including all options,
equipment, passengers and cargo).
The GVWR is shown on the
Safety Compliance Certification
Label located on the B-Pillar or
the edge of the driver’s door.
The GVW must never exceed the
GVWR.
GCW (Gross Combined Weight)– is the weight of the loaded vehicle
(GVW) plus the weight of the fully loaded trailer.
GCWR (Gross Combined Weight Rating)– is the maximum allowable
weight of the vehicle and the loaded trailer – including all cargo and
passengers – that the vehicle can handle without risking damage.
(Important: The towing vehicles’ braking system is rated for operation at
GVWR, not at GCWR. Separate functional brakes should be used for safe
control of towed vehicles and for trailers where the GCW of the towing
vehicle plus the trailer exceed the GVWR of the towing vehicle.The
GCW must never exceed the GCWR.
Maximum Loaded Trailer Weight– is the highest possible weight of a
fully loaded trailer the vehicle can tow. It assumes a vehicle with only
mandatory options, no cargo (internal or external), a tongue load of
10–15% (conventional trailer) or king pin weight of 15–25% (fifth wheel
trailer), and driver only (150 lb. [68 kg]).Consult your authorized
dealer (or theRV and Trailer Towing Guideprovided by your
authorized dealer) for more detailed information.
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Tongue Load or Fifth Wheel King Pin Weight– refers to the amount
of the weight that a trailer pushes down on a trailer hitch.
Examples:For a 5,000 lb. (2,268 kg) conventional trailer, multiply 5,000
by 0.10 and 0.15 to obtain a proper tongue load range of 500 to 750 lb.
(227 to 340 kg). For an 11,500 lb. (5,216 kg) fifth wheel trailer, multiply
by 0.15 and 0.25 to obtain a proper king pin load range of 1,725 to
2,875 lb. (782 to 1,304 kg)
Do not exceed the GVWR or the GAWR specified on the Safety
Compliance Certification Label.
Do not use replacement tires with lower load carrying capacities
than the originals because they may lower the vehicle’s GVWR
and GAWR limitations. Replacement tires with a higher limit than the
originals do not increase the GVWR and GAWR limitations.
Exceeding any vehicle weight rating limitation could result in
serious damage to the vehicle and/or personal injury.
Steps for determining the correct load limit:
1. Locate the statement “The combined weight of occupants and cargo
should never exceed XXX kg or XXX lbs.” on your vehicle’s placard.
2. Determine the combined weight of the driver and passengers that will
be riding in your vehicle.
3.
Subtract the combined weight of the driver and passengers from XXX kg
or XXX lbs.
4. The resulting figure equals the available amount of cargo and luggage
load capacity. For example, if the “XXX” amount equals 1,400 lbs. and
there will be five 150 lb. passengers in your vehicle, the amount of
available cargo and luggage load capacity is 650 lbs. (1,400–750 (5 x
150) = 650 lb.). In metric units (635–340 (5 x 68) = 295 kg.)
5. Determine the combined weight of luggage and cargo being loaded on
the vehicle. That weight may not safely exceed the available cargo and
luggage load capacity calculated in Step 4.
6. If your vehicle will be towing a trailer, load from your trailer will be
transferred to your vehicle. Consult this manual to determine how this
reduces the available cargo and luggage load capacity of your vehicle.
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Loaded vehicles may handle differently than unloaded vehicles.
Extra precautions, such as slower speeds and increased stopping
distance, should be taken when driving a heavily loaded vehicle.
Your vehicle can haul more cargo and people than most passenger cars.
Depending upon the type and placement of the load, hauling cargo and
people may raise the center of gravity of the vehicle.
TRAILER TOWING
Note:The trailer towing charts in this section apply to vehicles equipped
with gasoline engines; for vehicles equipped with diesel engines, refer to
your6.0/6.4 Liter Power Stroke Direct Injection Turbo Diesel Owner’s
Guide Supplement.
Your vehicle may tow a Conventional/Class IV trailer or fifth wheel trailer
provided the maximum trailer weight is less than or equal to the
maximum trailer weight listed for your engine and rear axle ratio on the
following charts.
To calculate your maximum trailer weight:
For pickup trucks:Take curb weight, hitch hardware and the driver’s
weight, then subtract them from the GCWR listed for your vehicle series,
engine, transmission and drive axle ratio(refer to the chart/table in the
following text). This calculation will give you the maximum trailer
weight possible for your vehicle.
For chassis cabs and pickup trucks with aftermarket equipment:
Weigh your vehicle at a certified scale and subtract this actual curb
weight, hitch hardware, and the driver’s weight from the GCWR listed for
your vehicle series, engine, transmission and drive axle ratio(refer to
the chart/table in the following text). This calculation will give you the
maximum trailer weight possible for your vehicle.
The weight of all additional cargo and passengers must be subtracted
from the maximum trailer weight calculated above.
Further trailer/hitch restrictions and limitations exist depending on the
type of trailer and hitch used. These additional maximum trailer weight
and tongue load limitations are listed in the chart/table that follows the
listing of GCWRs.
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. Refer to
Transmission fluid temperature gaugein theInstrument Cluster
chapter for the transmission fluid temperature information.
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Note:Do not exceed the GCWR listed for your vehicle on the following
chart/table, or the GVWR, GAWR or tire ratings specified on the Tire
Label or Safety Compliance Certification Label.
Towing trailers beyond the maximum recommended trailer
weight which exceeds the limit of the vehicle’s GCWR, GVWR,
GAWR or tire ratings could result in engine damage, transmission
damage, structural damage, loss of vehicle control, vehicle rollover and
personal injury.
Maximum GCWR - lb. (kg.)
Engine Rear axle
ratioManual
transmissionAutomatic
transmission
F–250 Pick-up
5.4L 3.73 15000 (6804) 16000 (7257)
4.10 17000 (7711) 18000 (8165)
6.8L 4.10 20000 (9072) 21000 (9525)
4.30 22000 (9979) 22500 (10206)
F–350 Single Rear Wheel (SRW) Pick-up
5.4L 3.73 15000 (6804) 16000 (7257)
4.10 17000 (7711) 18000 (8165)
6.8L 4.10 20000 (9072) 21000 (9525)
4.30 22000 (9979) 23000 (10433)
F–350 Dual Rear Wheel (DRW) Pick-up
5.4L 4.10 17500 (7938) 18500 (8391)
6.8L 4.10 20500 (9299) 21500 (9752)
4.30 22500 (10206) 23000 (10433)
F–350 Single Rear Wheel (SRW) Chassis Cab
5.4L 3.73 15000 (6804) 16000 (7257)
4.10 17000 (7711) 18000 (8165)
6.8L 4.10 20000 (9072) 21000 (9525)
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Maximum GCWR - lb. (kg.)
Engine Rear axle
ratioManual
transmissionAutomatic
transmission
F–350 Dual Rear Wheel (DRW) Chassis Cab
5.4L 3.73 15000 (6804) 16500 (7484)
4.10 17500 (7938) 18500 (8391)
6.8L 4.10 20500 (9299) 21500 (9752)
4.30 22500 (10206) 23000 (10433)
F–450 Chassis Cab/F–550
6.8L 4.88/5.38 26000 (11793) 26000 (11793)
Preparing to tow
Use the proper equipment for towing a trailer and make sure it is
properly attached to your vehicle. See your authorized dealer or a
reliable trailer dealer if you require assistance.
Hitches
ON PICK-UP TRUCKS, the trailer hitch provided on this vehicle
enhances collision protection for the fuel system. DO NOT
REMOVE!
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% for
conventional towing or 15%-25% fifth-wheel towing of the total weight of
the trailer is on the tongue.
Integrated hitch rating
The standard integrated hitch has two ratings depending on mode of
operation:
•Weight carrying- requires a draw bar and hitch ball. The draw bar
supports all the vertical tongue load of the trailer.
•Weight distributing- requires an aftermarket weight distributing
system which includes draw bar, hitch ball, spring bars and snap-up
brackets. The vertical tongue load of the trailer is distributed between
the truck and the trailer by this system.
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Hitch TypeMaximum
Gross Trailer
Weight — lb.
(kg)Maximum
Tongue Weight
— lb. (kg)
6.8L DRW
Pickup
2.5” ID without
adapter
(requires 2.5”
drawbar)Weight carrying 8000 (3629) 800 (363)
Weight
distributing15000 (6804) 1500 (680)
6.8L DRW
Pickup
2.5” ID with
adapter
(requires 2”
drawbar)Weight carrying 6000 (2721) 600 (272)
Weight
distributing12500 (5670) 1250 (567)
All SRW Pickups
and 5.4L DRW
Pickups
2” receiverWeight carrying 6000 (2721) 600 (272)
Weight
distributing12500 (5670) 1250 (567)
Towing trailers beyond the maximum tongue weight exceeds the
limit of the towing system and could result in vehicle structural
damage, loss of vehicle control and personal injury.
Weight distributing hitch
When hooking up a trailer using a weight distributing 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.
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
12” (13 mm) of the reference point.
After proper adjustment, the rear bumper should be no higher than in
Step 2.
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Note:Adjusting a weight distributing hitch so the rear bumper of the
vehicle is higher than it was unloaded will defeat the function of the
weight distributing hitch and may cause 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 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.
If you own a trailer with a hydraulic brake system, do not
connect the trailer’s hydraulic brake system directly to your
vehicle’s brake system. The vehicle’s brake system is only designed to
carry the appropriate amount of brake fluid for the vehicle alone.
Connecting a hydraulic trailer braking system could adversely affect
your vehicle’s braking performance.
The braking system of the tow vehicle is rated for operation at the
GVWR not GCWR.
Integrated trailer brake controller (if equipped)
Your vehicle may be equipped with a fully integrated electronic Trailer
Brake Controller (TBC). When used properly, the TBC helps ensure
smooth and effective trailer braking by powering the trailer’s electric
brakes with a proportional output based on the towing vehicle’s brake
pressure.
The Ford TBC has only been verified to be compatible with
trailers having electric-actuated drum brakes (one to four axles)
and not hydraulic surge or electric-over-hydraulic types. It is the
responsibility of the customer to ensure that the trailer brakes are
adjusted appropriately, functioning normally and all electric
connections are properly made.
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The TBC user interface consists of
the following:
1.+/- (GAIN adjustment
buttons):Pressing these buttons
will adjust the TBC’s power output
to the trailer brakes (in 0.5
increments). The GAIN setting can
be increased to a maximum of 10.0
or decreased to a minimum of 0 (no
trailer braking). Pressing and
holding a button will raise or lower
the setting continuously.
2.Trailer connection indicator:This lamp indicates trailer electrical
connection status.
•When a successful trailer connection is detected, the indicator will be
green.
•If the electrical connection is lost, the indicator will flash red. If the
connection is lost while the vehicle is stationary, the indicator will turn
off after 30 seconds. If the connection is lost while the vehicle is
moving, the indicator will flash until the ignition is turned off, then on
again or if there is a reconnection.
•If no electrical connection is detected after the ignition is turned on,
pressing a GAIN adjustment button will display the GAIN setting.
Sliding the manual control will display the GAIN setting, OUTPUT bar
graph and light the trailer indicator red.
3.GAIN setting display:Shows the current GAIN setting. This will
illuminate when a trailer is connected, flash if the trailer becomes
disconnected, or remain off if no trailer is connected.
4.OUTPUT bar graph:When the vehicle’s brake pedal is pushed, or
when the manual control is activated, green bar indicators will illuminate
to indicate the amount of power going to the trailer brakes relative to
the brake pedal or manual control input.
5.Manual control lever:Slide the control lever to the left to activate
power to the trailer’s electric brakes independent of the tow vehicle’s
brakes (see the followingProcedure for adjusting GAINsection for
instructions on proper use of this feature). If the manual control is
activated while the brake is also applied, the greater of the two inputs
determines the power sent to the trailer brakes.
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•Stop Lamps:Activating the TBC manual control lever will illuminate
both the trailer brake lamps and the tow vehicle brake lamps except
the Center High-Mount Stop Lamp (presuming proper trailer electrical
connection). Pressing the vehicle brake pedal will also illuminate both
trailer and vehicle brake lamps.
GAIN
The GAIN setting is used to set the TBC for the specific towing
condition and should be changed as towing conditions change. Changes
to towing conditions include trailer load, vehicle load, road conditions
and weather.
The GAIN should be set to provide the maximum trailer braking
assistance while ensuring the trailer wheels do not lock when braking.
Locked trailer wheels may lead to trailer instability.
Procedure for adjusting GAIN:
Note:This should only be performed in a traffic free environment at
speeds of approximately 20 – 25 mph (30 – 40 km/h).
1. Make sure the trailer brakes are in good working condition,
functioning normally, and properly adjusted. See your trailer dealer if
necessary.
2. Hook-up the trailer and make the electrical connections according to
the trailer manufacturer’s instructions.
3. When a trailer with electric brakes is plugged in, the trailer connection
indicator will illuminate green on the TBC and the GAIN setting display
will illuminate.
4. Use the GAIN adjustment (+/-) buttons to increase or decrease the
GAIN setting to the desired starting point. (A GAIN setting of 6.0 is a
good starting point for heavier loads.)
5. In a traffic-free environment, tow the trailer on a dry, level surface at
a speed of 20 – 25 mph (30 – 40 km/h) and squeeze the manual control
lever completely.
6. If the trailer wheels lock-up (indicated by squealing tires), reduce the
GAIN setting; if the trailer wheels turn freely, increase the GAIN setting.
Repeat Steps 5 and 6 until the GAIN setting is at a point just below
trailer wheel lock-up. If towing a heavier trailer, trailer wheel lockup may
not be attainable even with the maximum GAIN setting of 10.
Explanation of instrument cluster messages:
The TBC interacts with the instrument cluster message center. These
messages, accompanied by a single chime, will be displayed when the
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