
weight and the driver’s weight from the GCWR listed for your vehicle in
the following chart/table given its series, engine, transmission and drive
axle ratio. This calculation will give you the maximum trailer weight
possible for your vehicle.
The weight of all additional cargo, passengers and payload 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 temperature gaugein theInstrument Clusterchapter
for the transmission fluid temperature information.
The following trailer towing charts apply to vehicles equipped with
gasoline engines; for vehicles equipped with diesel engines, refer to your
6.0 Liter Power Stroke Direct Injection Turbo Diesel Owner’s Guide
Supplement.
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 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/F–350 Single Rear Wheel (SRW)
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)
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Maximum GCWR - lb. (kg.)
Engine Rear axle
ratioManual
transmissionAutomatic
transmission
F–350 Dual Rear Wheel (DRW)
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/F–550
6.8L 4.10/4.30 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 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% for
conventional towing or 20%-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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Maximum Trailer/Hitch Limits
Trailer/Hitch
TypeF-250/F-350
Single Rear
Wheel (SRW)F-350 Dual
Rear Wheel
(DRW)F-450/F-550
Conventional 12500 (5670) 12500 (5670) 16000 (7257)
5th
Wheel/Goose-
neckSee manufacturer’s recommendations
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.
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.
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
1 2” (13 mm) 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 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.
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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.
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). The TBC assures 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 TBC can only be used with electric trailer brakes (one to
four axles) and not surge or electric-over-hydraulic types as
these may lose trailer braking ability. It is the responsibility of the
customer to ensure that the trailer brakes are functioning properly and
all electric connections are properly made.
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.
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•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.
•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. 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.
•Stop Lamps:Both the tow vehicle and the trailer brake lamps will be
illuminated in the event of a manual apply using the TBC manual
control lever, as well as with any activation of the vehicle brake pedal.
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.
1. Make sure the trailer brakes are in good working condition 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.
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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. Tow the trailer on a dry, level surface at 25 mph (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 wheels turn freely, increase the GAIN setting. Repeat
Steps 5 and 6 until the GAIN setting is at a point just below wheel
lock-up. If towing a heavier trailer wheel lockup may not be attainable
and the gain should be set as to achieve maximum braking force for the
specific towing conditions.
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
TBC determines a malfunction in the trailer connection, TBC system, or
in the trailer. These messages are listed below:
TRAILER DISCONNECTED (if equipped with message center) or
CHECK TRAILER (if equipped with mini message center):This
message is displayed when a trailer connection was determined and then
a disconnection, either intentionally or unintentionally, has been sensed
during a given ignition cycle. This message is also displayed during
manual activation without a trailer connected.
TBC FAULT: This message is displayed in response to faults sensed by
the TBC. In the event this message is seen, please take your vehicle to
an authorized Ford dealership for diagnosis and repair.
TRAILER FAULT: The TBC is capable of determining certain faults in
the trailer wiring/brake system. This message is displayed when one of
the following faults has occurred:
• Short circuit on the electric brake output wire: If the TRAILER
FAULT message is displayed with no trailer connected, the problem is
with the wiring from the TBC to the 7–pin connector in the bumper. If
the message is displayed with a trailer connected, the problem is
related to the trailer wiring; consult your trailer dealer for assistance.
• Trailer brake overload: The trailer brakes are drawing too much
current; consult your trailer dealer for assistance.
Note: Your TBC can be diagnosed by your authorized Ford dealership to
determine exactly which trailer fault has occurred; however, this
diagnosis is notcovered under your Ford warranty.
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Points to Remember:
•Brake System Interaction:The TBC interacts with the brake
system of the vehicle, including ABS. Therefore, if these systems are
not functioning properly the TBC may not function at full
performance.
•Ignition Off:When the vehicle is turned off, the TBC Output is
disabled and the display is shut down. Reactivation of the ignition
from OFF to RUN will awaken the TBC module.
•Factory Installed:The TBC is only a factory installed item. Ford is
not responsible for warranty or performance of the TBC due to misuse
or out-of-factory installation.
Trailer lamps
Trailer lamps are required on most towed vehicles. 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.
Using a step bumper (if equipped)
The rear bumper is equipped with an integral hitch and only requires a
ball with a one inch (25.4 mm) shank diameter. The bumper has a 5,000
lb. (2,270 kg) trailer weight and 500 lb. (227 kg) tongue weight capacity.
If it is necessary to relocate the trailer hitch ball position, a
frame-mounted trailer hitch must be installed.
Driving while you tow
When towing a trailer:
•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, activate the Tow/Haul
feature. This will also assist in transmission cooling. (For additional
information, refer to theUnderstanding the positions of the 5–speed
automatic transmissionsection in this chapter.
•Anticipate stops and brake gradually.
•Do not exceed the GCWR rating or transmission damage may occur.
•Your vehicle may be equipped with a temporary or conventional spare
tire. If the spare tire is different in size (diameter and/or width), tread
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type (All-Season or All-Terrain) or is from a different manufacturer
other than the road tires on your vehicle, your spare tire is considered
“temporary”. Consult information on the spare tire label for limitations
when using.
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.
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 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)
(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 6 inches (15 cm) above the
bottom edge of the rear bumper.
•Disconnect the trailer tow electrical connector to prevent blown fuses
caused by water entering into your trailer’s electrical wiring.
Exceeding these limits may allow water to enter critical vehicle
components, adversely affecting driveability, emissions and reliability.
Replace front and rear axle lubricants any time the axles have been
submerged in water. Axle lubricant quantities are not to be checked
unless a leak is suspected.
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