2012 FORD F550 brake

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 vehicle’s 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 the RV and Trailer Towing Guide provided by your
authorized dealer) for more detailed information.
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)
WARNING: Do not exceed the GVWR or the GAWR specified on
the Safety Compliance Certification Label. Tires, Wheels and Loading
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TRAILER TOWING
Note: The trailer towing chart in this section applies to vehicles
equipped with a gasoline engine; for vehicles equipped with a diesel
engine, refer to your diesel 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 for your engine and rear axle ratio.
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 gauge in the Instrument Cluster
chapter for the transmission fluid temperature information.
To find the maximum trailer weight allowed for your vehicle, consult
your authorized dealer (or the RV and Trailer Towing Guide provided
by your authorized dealer).
To calculate your maximum trailer weight on your own:
1. Pick-up trucks: Take curb weight, hitch hardware and the driver’s
weight, then subtract them from the GCWR listed for your vehicle
series and drive axle ratio listed on the following table.
2.
Chassis cabs and pick-up 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 and drive axle ratio listed on the following table.
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. This information follows the table listing
the maximum GCWRs.
For load specification terms found on the label and instructions on
calculating your vehicle’s load, refer to Vehicle loading - with and without
a trailer in this chapter when figuring the total weight of your vehicle.
Note: Do not exceed the tire ratings specified on the Tire Label or
Safety Compliance Certification Label.
WARNING: Do not exceed the GVWR or the GAWR specified on
the certification label.Tires, Wheels and Loading
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Safety Chains
Note: Do not attach safety chains to the bumper.
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.
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.
WARNING: 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, which could result in loss of
vehicle control, crash or serious injury.
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 been tested to be compatible with several major
brands of electric-over-hydraulic trailer brakes; contact your authorized
dealer for information on which brands can be used.
WARNING: The Ford TBC has been verified to be compatible
with trailers having electric-actuated drum brakes (one to four
axles) and some electric-over-hydraulic types, but not hydraulic surge
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. Failure to do so may result in loss of
vehicle control, crash or serious injury.Tires, Wheels and Loading
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The TBC user interface consists of
the following:
1. +/- (GAIN adjustment
buttons): Pressing these buttons
adjusts 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 raises or lowers the setting continuously. The gain
setting displays in the message center as follows: TBC GAIN = XX.X.
The trailer brake controller (TBC) is designed to display three items of
information in the instrument cluster message center. These are: gain
setting, output bar graph, and trailer connectivity status. They appear in
the message center as follows:
• TBC GAIN = XX.X NO TRAILER: The instrument cluster message
center displays the current gain setting during a given ignition cycle
and when adjusting the gain. This message is also displayed during
manual activation without a trailer connected or when gain
adjustments are made with no trailer connected.
• TBC GAIN = XX.X OUTPUT = //////: When the vehicle’s brake pedal
is pushed, or when the manual control is activated, bar indicators
illuminate in the instrument cluster message center to indicate the
amount of power going to the trailer brakes relative to the brake pedal
or manual control input. One bar indicates the least amount of output
with six bars indicating maximum output.
• TRAILER CONNECTED: This message is displayed when a correct
trailer wiring connection (a trailer with electric trailer brakes) has
been sensed during a given ignition cycle.
• TRAILER DISCONNECTED: This message is displayed and
accompanied by a single chime, when a trailer connection was
determined and then a disconnection, either intentionally or
unintentionally, has been sensed during a given ignition cycle. It is also
displayed if a truck or trailer wiring fault occurs causing the trailer to
appear disconnected. This message is also displayed during manual
activation without a trailer connected. Tires, Wheels and Loading
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2. 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 following Procedure for adjusting GAIN section 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.
• Stop lamps: Activating the TBC manual control lever illuminates 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 also illuminates both
trailer and vehicle brake lamps.
Procedure for adjusting 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.
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
CONNECTED message displays in the instrument cluster message center.
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 lock-up
may not be attainable even with the maximum GAIN setting of 10.Tires, Wheels and Loading
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Explanation of instrument cluster warning messages:
The TBC interacts with the instrument cluster message center to display
the following messages:
TRAILER BRAKE MODULE FAULT: This message is displayed and
accompanied by a single chime, in response to faults sensed by the TBC.
In the event this message is seen, please contact your authorized dealer
as soon as possible for diagnosis and repair. The TBC may still function,
but performance may be degraded.
WIRING FAULT ON TRAILER: This message is displayed when a
Short circuit on the electric brake output wire has occurred. If the
WIRING FAULT ON TRAILER message is displayed and accompanied
by a single chime, with no trailer connected, the problem is with the
vehicle wiring from the TBC to the 7–pin connector at the bumper. If the
message is only displayed with a trailer connected, the problem is related
to the trailer wiring; consult your trailer dealer for assistance. This can
be a short to ground (i.e., chaffed wire) or a short to voltage (i.e., pulled
pin on trailer emergency break-away battery) or trailer brakes drawing
too much current.
Note: Your TBC can be diagnosed by your authorized dealer to
determine exactly which trailer fault has occurred; however, if the fault
is with the trailer this diagnosis is not covered under your Ford
warranty.
Points to Remember:
• Remember to adjust gain setting before using the TBC for the first
time.
• Readjust gain setting on the TBC (according to procedure above)
whenever road, weather and trailer or vehicle loading conditions
change from those that existed when the gain was initially set.
• The sliding lever on the TBC should be used only for manual
activation of trailer brakes to assist with proper adjustment of the
GAIN. Misuse, such as application during trailer sway, could cause
instability of trailer and/or tow vehicle.
• Avoid towing in adverse weather conditions. The TBC does not
provide anti-lock control of the trailer wheels. Trailer wheels can lock
up on slippery surfaces, resulting in reduced stability of trailer and
tow vehicle.
• The TBC is equipped with a feature which reduces output at vehicle
speeds below 11 mph (18 km/h) so trailer and vehicle braking is not
jerky or harsh. This feature is only available when applying the brakes
using the vehicle’s brake pedal, not the TBC. Tires, Wheels and Loading
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• The TBC interacts with the brake system of the vehicle, including
ABS, in order to reduce the likelihood of trailer wheel lock-up;
therefore, if these systems are not functioning properly, the TBC may
not function at full performance.
• Your vehicle’s brake system and the trailer brake system work
independently of each other; changing the GAIN setting on the TBC
does not affect the operation of your vehicle’s brakes whether a trailer
is attached or not.
• When the vehicle is turned off, the TBC output is disabled and the
display is shut down; turning the ignition from off to on awakens the
TBC module.
• The TBC is only a factory- or dealer-installed item; Ford is not
responsible for warranty or performance of the TBC due to misuse or
customer installation.
• Do not attempt removal of the TBC without consulting the
Workshop Manual; damage to the unit may result.
Trailer Lamps
Trailer lamps are required on most towed vehicles. Make sure all running
lights, brake lights, turn signals and hazard lights are working. Contact
your authorized dealer or trailer rental agency for proper instructions
and equipment for hooking-up trailer lamps.
Driving while you tow
When towing a trailer:
• Consult your local motor vehicle laws for towing a trailer.
• Do not drive faster than 70 mph (113 km/h) during the first 500 miles
(800 km) of trailer towing 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.
• Activate the tow/haul feature to eliminate excessive transmission
shifting and assist in transmission cooling. For additional information,
refer to Automatic transmission operation in the Driving chapter.
• Allow more distance for stopping with a trailer attached; anticipate
stops and brake gradually.Tires, Wheels and Loading
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Braking
• Anticipate stops; allow more distance and time to stop than normal.
• Do not apply the trailer brakes for extended periods of time as they
can overheat and lose effectiveness.
• The trailer brakes (including the shoes, drum and trailer brake
magnets) must be inspected and serviced at intervals specified by the
manufacturer.
• Electric brakes also require periodic adjustment to keep the shoes
properly spaced. If the brakes get hot when driving or if they will not
hold, chances are that they need adjustment.
Backing-up
• Practice backing-up, particularly if you are a novice. Turn the steering
wheel to the right to move the trailer’s rear end to the right.
• Sharp steering movements may cause the trailer to jackknife or go out
of control.
Tires
• Select tires that meet the trailer loading requirements.
• All trailer tires should be of the same size, and construction.
• Always check tow vehicle and trailer tire pressure before towing.
Launching or Retrieving a Boat or Personal Water Craft (PWC)
Note: Disconnect the wiring to the trailer before backing the trailer into
the water.
Note: Reconnect the wiring to the trailer after the trailer is removed
from the water.
When backing down a ramp during boat launching or retrieval:
1. Do not allow the static water level to rise above the bottom edge of
the rear bumper.
2. Do not allow waves to break higher than six inches (15 centimeters)
above the bottom edge of the rear bumper.
Exceeding these limits may allow water to enter vehicle components:
1. Causing internal damage to the components.
2. Affecting driveability, emissions, and reliability.
Replace the rear axle lubricant any time the rear axle has been
submerged in water. Water may have contaminated the rear axle
lubricant, which is not normally checked or changed unless a leak is
suspected or other axle repair is required.Tires, Wheels and Loading
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