2008 FORD SUPER DUTY tire size

Note:You may not find this information on all tires because it is not
required by federal law.
Letter rating Speed rating - mph (km/h)
M 81 mph (130 km/h)
N 87 mph (140 km/h)
Q 99 mph (159 km/h)
R 106 mph (171 km/h)
S 112 mph (180 km/h)
T 118 mph (190 km/h)
U 124 mph (200 km/h)
H 130 mph (210 km/h)
V 149 mph (240 km/h)
W 168 mph (270 km/h)
Y 186 mph (299 km/h)
Note:For tires with a maximum speed capability over 149 mph
(240 km/h), tire manufacturers sometimes use the letters ZR. For
those with a maximum speed capability over 186 mph (299 km/h), tire
manufacturers always use the letters ZR.
8.U.S. DOT Tire Identification Number (TIN):This begins with the
letters “DOT” and indicates that the tire meets all federal standards. The
next two numbers or letters are the plant code designating where it was
manufactured, the next two are the tire size code and the last four
numbers represent the week and year the tire was built. For example,
the numbers 317 mean the 31st week of 1997. After 2000 the numbers
go to four digits. For example, 2501 means the 25th week of 2001. The
numbers in between are identification codes used for traceability. This
information is used to contact customers if a tire defect requires a recall.
9.M+S or M/S:Mud and Snow, or
AT:All Terrain, or
AS:All Season.
10.Tire Ply Composition and Material Used:Indicates the number of
plies or the number of layers of rubber-coated fabric in the tire tread and
sidewall. Tire manufacturers also must indicate the ply materials in the
tire and the sidewall, which include steel, nylon, polyester, and others.
11.Maximum Load:Indicates the maximum load in kilograms and
pounds that can be carried by the tire. Refer to the Tire Label or Safety
Compliance Certification Label, which is located on the B-Pillar or the
edge of the driver’s door, for the correct tire pressure for your vehicle.
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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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Note:Do not use snow chains on front tires of vehicles with 20” wheels
and tires.
The tires on your vehicle have all weather treads to provide traction in
rain and snow. However, in some climates, you may need to use snow
tires and chains. If you need to use chains, it is recommended that steel
wheels (of the same size and specifications) be used, as chains may chip
aluminum wheels.
Follow these guidelines when using snow tires and chains:
•Use only SAE Class S chains.
•Install chains securely, verifying that the chains do not touch any
wiring, brake lines or fuel lines.
•Drive cautiously. If you hear the chains rub or bang against your
vehicle, stop and re-tighten the chains. If this does not work, remove
the chains to prevent damage to your vehicle.
•If possible, avoid fully loading your vehicle.
•Remove the tire chains when they are no longer needed. Do not use
tire chains on dry roads.
•The suspension insulation and bumpers will help prevent vehicle
damage. Do not remove these components from your vehicle when
using snow tires and chains.
VEHICLE LOADING – WITH AND WITHOUT A TRAILER
This section will guide you in the proper loading of your vehicle and/or
trailer, to keep your loaded vehicle weight within its design rating
capability, with or without a trailer. Properly loading your vehicle will
provide maximum return of vehicle design performance. Before loading
your vehicle, familiarize yourself with the following terms for determining
your vehicle’s weight ratings, with or without a trailer, from the vehicle’s
Tire Label or Safety Compliance Certification Label:
Base Curb Weight– is the weight of the vehicle including a full tank of
fuel and all standard equipment. It does not include passengers, cargo, or
optional equipment.
Vehicle Curb Weight– is the weight of your new vehicle when you
picked it up from your authorized dealer plus any aftermarket
equipment.
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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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Loading
•Keep the center-of-gravity low for best handling.
•Trailer loads should be evenly distributed front to back and left to
right.
•The load distribution within the trailer should be such that 10%–15%
of the trailer weight is on the hitch. (15%–25% for fifth-wheel or
gooseneck towing.)
•Never exceed truck, trailer, receiver, ball, tongue, tire or coupler
loading recommendations.
Braking
•The trailer brakes must be inspected and serviced at intervals
specified by the manufacturer. This includes the shoes, drum and
trailer brake magnets.
•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.
•Anticipate the need to stop; allow much 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.
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
•All trailer tires should be of the same size, and construction.
•Select tires that meet the trailer loading requirements.
•Always check tow vehicle and trailer tire pressure before towing.
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.
2008 F-250/350/450/550(f23)
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box Description
66 — Not used
67 — Not used
68 — Not used
69 — Not used
70 10A**Gasoline engines:A/C clutch relay coil,
Refrigerant Containment Switch, Heated
PCV
Diesel engine:A/C clutch relay coil,
Clutch switch, Fuel pump cooler, A/C
cycle pressure switch
71 5A** Fuel pump relay diode, PCM/ECM
Run/Start power
72 15A**Gasoline engines:Ignition coils
Diesel engine:Engine TCM
73 — Not used
74 20A**Gasoline engines:VPWR: HEGO, CMS,
MAFS, EVMV, CMCV, VCT, IMTV
Diesel engine:VPWR: Engine loads
75 5A** Back-up relay coil power
76 20A**Gasoline engines:VPWR: PCM
Diesel engine:VPWR: ECM
77 10A** ABS module logic
* Cartridge fuses ** Mini fuses
CHANGING A FLAT TIRE
If you get a flat tire while driving:
•do not brake heavily.
•gradually decrease the vehicle’s speed.
•hold the steering wheel firmly.
•slowly move to a safe place on the side of the road.
Your vehicle may be equipped with a conventional spare tire that is
different in one or more of the following: type, brand, size, speed rating
and tread design. If this is the case, this dissimilar spare tire is still rated
for your vehicle loads (GAWR and GVWR).
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The use of tire sealants may damage your tires.
Dissimilar spare tire/wheel information
Failure to follow these guidelines could result in an increased
risk of loss of vehicle control, injury or death.
If you have a dissimilar spare tire/wheel, then it is intended for
temporary use only. This means that if you need to use it, you should
replace it as soon as possible with a road tire/wheel that is the same size
and type as the road tires and wheels that were originally provided by
Ford. If the dissimilar spare tire or wheel is damaged, it should be
replaced rather than repaired.
A dissimilar spare tire/wheel is defined as a spare tire and/or wheel that
is different in brand, size or appearance from the road tires and wheels
and can be one of three types:
1.T-type mini-spare:This spare tire begins with the letter “T” for tire
size and may have “Temporary Use Only” molded in the sidewall
2.Full-size dissimilar spare with label on wheel:This spare tire has
a label on the wheel that states: “THIS TIRE AND WHEEL FOR
TEMPORARY USE ONLY”
When driving with one of the dissimilar spare tires listed above,do not:
•Exceed 50 mph (80 km/h)
•Load the vehicle beyond maximum vehicle load rating listed on the
Safety Compliance Label
•Use snow chains on the end of the vehicle with the dissimilar spare
tire
•Use more than one dissimilar spare tire at a time
•Use commercial car washing equipment
•Try to repair the dissimilar spare tire
Use of one of the dissimilar spare tires listed above at any one wheel
location can lead to impairment of the following:
•Handling, stability and braking performance
•Comfort and noise
•Ground clearance and parking at curbs
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•Winter weather driving capability
•Wet weather driving capability
It is not recommended that the vehicle be operated in 4WD modes with
a temporary emergency spare tire. If 4WD operation is necessary, do not
operate above speeds of 10 mph (16 km/h) or for distances above
50 miles (80 km).
3.Full-size dissimilar spare without label on wheel
When driving with the full-size dissimilar spare tire/wheel,do not:
•Exceed 70 mph (113 km/h)
•Use more than one dissimilar spare tire/wheel at a time
•Use commercial car washing equipment
•Use snow chains on the end of the vehicle with the dissimilar spare
tire/wheel
The usage of a full-size dissimilar spare tire/wheel can lead to
impairment of the following:
•Handling, stability and braking performance
•Comfort and noise
•Ground clearance and parking at curbs
•Winter weather driving capability
•Wet weather driving capability
•All-Wheel driving capability (if applicable)
•Load leveling adjustment (if applicable)
When driving with the full-size dissimilar spare tire/wheel additional
caution should be given to:
•Towing a trailer
•Driving vehicles equipped with a camper body
•Driving vehicles with a load on the cargo rack
Drive cautiously when using a full-size dissimilar spare tire/wheel and
seek service as soon as possible.
Stopping and securing the vehicle
To help prevent the vehicle from moving when you change a tire,
be sure the parking brake is set, then block (in both directions)
the wheel that is diagonally opposite to the tire being changed.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
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