2008 FORD SUPER DUTY tire type

Information on “T” type tires
“T” type tires have some additional
information beyond those of “P”
type tires; these differences are
described below:
T145/80D16 is an example of a tire
size.
Note:The temporary tire size for
your vehicle may be different from
this example.
1.T:Indicates a type of tire,
designated by the Tire and Rim
Association (T&RA), that is
intended for temporary service on
cars, SUVs, minivans and light
trucks.
2.145:Indicates the nominal width
of the tire in millimeters from
sidewall edge to sidewall edge. In general, the larger the number, the
wider the tire.
3.80:Indicates the aspect ratio which gives the tire’s ratio of height to
width. Numbers of 70 or lower indicate a short sidewall.
4.D:Indicates a “diagonal” type tire.
R:Indicates a “radial” type tire.
5.16:Indicates the wheel or rim diameter in inches. If you change your
wheel size, you will have to purchase new tires to match the new wheel
diameter.
Location of the Tire Label or Safety Compliance Certification Label
You will find a Tire Label or Safety Compliance Certification Label
containing tire inflation pressure by tire size and other important
information located on the B-Pillar or the edge of the driver’s door. Refer
to the payload description and graphic in theVehicle loading — with
and without a trailersection.
SNOW TIRES AND CHAINS
Snow tires must be the same size and grade as the tires you
currently have on your vehicle.
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The following gives you a few examples on how to calculate the available
amount of cargo and luggage load capacity:
•Another example for your vehicle with 1,400 lb. (635 kg) of cargo and
luggage capacity. You decide to go golfing. Is there enough load
capacity to carry you, 4 of your friends and all the golf bags? You and
four friends average 220 lb. (99 kg) each and the golf bags weigh
approximately 30 lb. (13.5 kg) each. The calculation would be: 1,400 –
(5 x 220) – (5 x 30) = 1,400 – 1,100 – 150 = 150 lb. Yes, you have
enough load capacity in your vehicle to transport four friends and
your golf bags. In metric units, the calculation would be: 635 kg — (5
x 99 kg) — (5 x 13.5 kg) = 635 — 495 — 67.5 = 72.5 kg.
•A final example for your vehicle with 1,400 lb. (635 kg) of cargo and
luggage capacity. You and one of your friends decide to pick up
cement from the local home improvement store to finish that patio
you have been planning for the past 2 years. Measuring the inside of
the vehicle with the rear seat folded down, you have room for
12-100 lb. (45 kg) bags of cement. Do you have enough load capacity
to transport the cement to your home? If you and your friend each
weigh 220 lb. (99 kg), the calculation would be: 1,400 – (2 x 220) –
(12 x 100) = 1,400 – 440 – 1,200 = – 240 lb. No, you do not have
enough cargo capacity to carry that much weight. In metric units, the
calculation would be: 635 kg — (2 x 99 kg) — (12 x 45 kg) = 635 —
198 — 540 = —103 kg. You will need to reduce the load weight by at
least 240 lb. (104 kg). If you remove 3-100 lb. (45 kg) cement bags,
then the load calculation would be:
1,400 – (2 x 220) – (9 x 100) = 1,400 – 440 – 900 = 60 lb. Now you
have the load capacity to transport the cement and your friend home.
In metric units, the calculation would be: 635 kg — (2 x 99 kg) — (9
x 45 kg) = 635 — 198 — 405 = 32 kg.
The above calculations also assume that the loads are positioned in your
vehicle in a manner that does not overload the Front or the Rear Gross
Axle Weight Rating specified for your vehicle on the Tire Label or Safety
Compliance Certification Label found on the edge of the driver’s door.
Special loading instructions for owners of pickup trucks and
utility-type vehicles
For important information regarding safe operation of this type
of vehicle, see thePreparing to drive your vehiclesection in
theDrivingchapter of this owner guide.
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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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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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information, refer to theUnderstanding the shift positions of the
5–speed automatic transmissionsection in theDrivingchapter.
•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
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 or Safety
Compliance Certification 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
informationfor more information.
Trailer towing safety tips
General
•Ensure that the trailer, safety chains and 7–pin electrical connectors
are securely fastened.
•Make sure the truck receiver, draw bar, and coupler are properly
connected and adjusted.
•Check rear view and side mirrors for proper visibility especially when
towing trailer wider than the truck.
•When towing, operate the vehicle at lower speeds than you would
when not towing a trailer. The likelihood of trailer sway is greater at
higher speeds.
•If you will be towing a trailer frequently in hot weather, hilly
conditions, at GCWR, or any combination of these factors, consider
refilling your rear axle with synthetic gear lubricant if not already so
equipped. Refer toMaintenance Product Specifications and
Capacitiesin theMaintenance and Specificationschapter for the
proper axle lubricant. Remember that regardless of the rear axle
lubricant used, do not tow a trailer for the first 500 miles (800 km) of
a new vehicle, and that the first 500 miles of towing be done at no
faster than 70 mph (112 km/h) with no full-throttle starts.
•When turning make wide turns to allow trailer tires to properly clear
any obstacles.
•Be prepared for trailer sway due to buffeting when larger vehicles
pass in either direction.
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torque features which may not be re-used). Never re-use a bolt or nut.
Torque fasteners to specifications inWorkshop Manual.
A high crown in the road or high crosswinds may also make the steering
seem to wander/pull.
TRACTION-LOK AXLE (IF EQUIPPED)
This axle provides added traction on slippery surfaces, particularly when
one wheel is on a poor traction surface. Under normal conditions, the
Traction-Lok axle functions like a standard rear axle. The axle may
exhibit a slight noise or vibration in tight turns with low vehicle speed.
This is normal behavior and indicates the axle is working.
PREPARING TO DRIVE YOUR VEHICLE
Utility vehicles have a significantly higher rollover rate than
other types of vehicles.
In a rollover crash, an unbelted person is significantly more likely
to die than a person wearing a seat belt.
Utility vehicles and trucks have larger tires and increased ground
clearance, giving the vehicle a higher center of gravity than a passenger
car.
Vehicles with a higher center of gravity such as utility and trucks
handle differently than vehicles with a lower center of gravity.
Utility vehicles and trucks arenotdesigned for cornering at speeds as
high as passenger cars any more than low-slung sports cars are
designed to perform satisfactorily under off-road conditions. Avoid
sharp turns, excessive speed or abrupt maneuvers in these vehicles.
Failure to drive cautiously could result in an increased risk of loss of
vehicle control, vehicle rollover, personal injury and death.
Loaded vehicles, with a higher center of gravity, may handle
differently than unloaded vehicles. Do not overload your vehicle
and use extra precautions, such as driving at slower speeds, avoiding
abrupt steering changes and allowing for increased stopping distance,
when driving a heavily loaded vehicle. Over loading or loading the
vehicle improperly can deteriorate handling capability and contribute
to loss of vehicle control and vehicle rollover.
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If your vehicle sustains damage to the rear bumper/fascia, leaving
it misaligned or bent, the sensing zone may be altered causing
inaccurate measurement of obstacles or false alarms.
FOUR-WHEEL DRIVE (4WD) OPERATION (IF EQUIPPED)
For important information regarding safe operation of this type
of vehicle, seePreparing to drive your vehiclein this chapter.
When four–wheel drive (4WD) is engaged, power is supplied to all four
wheels through a transfer case. 4WD can be selected when additional
traction is desired.
4WD operation is not recommended on dry pavement. Doing so could
result in difficult disengagement of the transfer case, increased tire wear
and decreased fuel economy.
Manual Shift On Stop (MSOS) 4x4 system (if equipped)
The 4WD system is engaged or
disengaged by rotating the control
for both front wheel hub locks from
the FREE or LOCK position, then
manually engaging or disengaging
the transfer case with the
floor-mounted shifter. For increased
fuel economy in 2WD, rotate both
hub locks to the FREE position.
•For proper operation, make
sure that each hub is fully
engaged and that both hub locks are set to the same position
(both set to LOCK or both set to FREE). To engage LOCK,
turn the hub locks completely clockwise; to disengage the hubs
(FREE), turn the hub locks completely counterclockwise.
•Some vehicles may be equipped with wheel ornaments that cover the
4x4 manual hub lock. These ornaments must be removed to access
the manual hub locks.
Electronic Shift On the Fly (ESOF) 4x4 system (if equipped)
If equipped with the electronic shift 4WD System, and the
instrument panel control is moved to 4X4 LOW while the vehicle
is moving above 5 mph (8 km/h), the system will not engage and
no damage will occur to the 4WD system. Before 4X4 LOW can be
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