12.Treadwear, Traction and Temperature Grades
•Treadwear:The treadwear grade is a comparative rating based on the
wear rate of the tire when tested under controlled conditions on a
specified government test course. For example, a tire graded 150
would wear one and one-half (1
1 2) times as well on the government
course as a tire graded 100.
•Traction:The traction grades, from highest to lowest are AA, A, B,
and C. The grades represent the tire’s ability to stop on wet pavement
as measured under controlled conditions on specified government test
surfaces of asphalt and concrete. A tire marked C may have poor
traction performance.
•Temperature:The temperature grades are A (the highest), B and C,
representing the tire’s resistance to the generation of heat and its
ability to dissipate heat when tested under controlled conditions on a
specified indoor laboratory test wheel.
13.Maximum Permissible Inflation Pressure:Indicates the tire
manufacturers’ maximum permissible pressure and/or the pressure at
which the maximum load can be carried by the tire. This pressure is
normally higher than the manufacturer’s recommended cold inflation
pressure which can be found on either the tire label or certification label
which is located on the B-Pillar or the edge of the driver’s door. The cold
inflation pressure should never be set lower than the recommended
pressure on the vehicle label.
The tire suppliers may have additional markings, notes or warnings such
as standard load, radial tubeless, etc.
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Additional information contained on the tire sidewall for “LT” type
tires
“LT” type tires have some additional
information beyond those of “P”
type tires; these differences are
described below:
1.LT:Indicates a tire, designated by
the Tire and Rim Association
(T&RA), that is intended for service
on light trucks.
2.Load Range/Load Inflation
Limits:Indicates the tire’s
load-carrying capabilities and its
inflation limits.
3.Maximum Load Dual lb. (kg)
at psi (kPa) cold:Indicates the
maximum load and tire pressure
when the tire is used as a dual;
defined as four tires on the rear axle (a total of six or more tires on the
vehicle).
4.Maximum Load Single lb. (kg) at psi (kPa) cold:Indicates the
maximum load and tire pressure when the tire is used as a single;
defined as two tires (total) on the rear axle.
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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
You will find a tire 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.
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Safety practices
Driving habits have a great deal to do with your tire mileage and safety.
•Observe posted speed limits
•Avoid fast starts, stops and turns
•Avoid potholes and objects on the road
•Do not run over curbs or hit the tire against a curb when parking
If your vehicle is stuck in snow, mud, sand, etc.,do notrapidly
spin the tires; spinning the tires can tear the tire and cause an
explosion. A tire can explode in as little as three to five seconds.
Never spin the tires in excess of the 35 mph (55 km/h) point
indicated on the speedometer.
Highway hazards
No matter how carefully you drive there’s always the possibility that you
may eventually have a flat tire on the highway. Drive slowly to the
closest safe area out of traffic. This may further damage the flat tire, but
your safety is more important.
If you feel a sudden vibration or ride disturbance while driving, or you
suspect your tire or vehicle has been damaged, immediately reduce your
speed. Drive with caution until you can safely pull off the road. Stop and
inspect the tires for damage. If a tire is under-inflated or damaged,
deflate it, remove wheel and replace it with your spare tire and wheel. If
you cannot detect a cause, have the vehicle towed to the nearest repair
facility or tire dealer to have the vehicle inspected.
Tire and wheel alignment
A bad jolt from hitting a curb or pothole can cause the front end of your
vehicle to become misaligned or cause damage to your tires. If your
vehicle seems to pull to one side when you’re driving, the wheels may be
out of alignment. Have a qualified technician at a Ford or
Lincoln/Mercury dealer check the wheel alignment periodically.
Wheel misalignment in the front or the rear can cause uneven and rapid
treadwear of your tires and should be corrected by a qualified technician
at a Ford or Lincoln/Mercury dealer. Front wheel drive (FWD) vehicles
and those with an independent rear suspension (if equipped) may
require alignment of all four wheels.
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•DRW – Six tire rotation
If your vehicle is equipped with dual
rear wheels it is recommended that
front and rear tires (in pairs) be
rotated only side to side, with the
rear tires maintaining original
vehicle position. After tire rotation,
inflation pressures must be adjusted
for the tires new positions in
accordance with vehicle
requirements.
Sometimes irregular tire wear can be corrected by rotating the tires.
Note:If your tires show uneven wear ask a qualified technician at a
reputable repair facility to check for and correct any wheel misalignment,
tire imbalance or mechanical problem involved before tire rotation.
Note:Your vehicle may be equipped with a dissimilar spare tire/wheel. 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. If
you have a dissimilar spare tire/wheel it is intended for temporary use
only and should not be used in a tire rotation.
Note:After having your tires rotated, inflation pressure must be checked
and adjusted to the vehicle requirements.
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If you’re parking your vehicle on a grade or with a trailer, press and hold
the brake pedal down, then set the parking brake. There may be a little
vehicle movement as the parking brake sets to hold the vehicle’s weight.
This is normal and should be no reason for concern. If needed, press and
hold the service brake pedal down, then try reapplying the parking
brake. Chock the wheels if required. If the parking brake cannot hold the
weight of the vehicle, the parking brake may need to be serviced or the
vehicle may be overloaded.
STEERING
To prevent damage to the power steering system:
•Never hold the steering wheel at its furthest turning points (until it
stops) for more than a few seconds when the engine is running.
•Do not operate the vehicle with a low power steering pump fluid level
(below the FULL COLD mark on the dipstick).
If the power steering system breaks down (or if the engine is turned
off), you can steer the vehicle manually, but it takes more effort.
If the steering wanders or pulls, check for:
•an improperly inflated tire
•uneven tire wear
•loose or worn suspension components
•loose or worn steering components
•improper steering alignment
If any steering components are serviced or replaced, install new
fasteners (many are coated with thread adhesive or have prevailing
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.
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Power is supplied to all four wheels
through a transfer case. On 4WD
vehicles, the transfer case allows
you to select 4WD when necessary.
Information on transfer case
operation and shifting procedures
can be found in theDriving
chapter. Information on transfer
case maintenance can be found in theMaintenance and Specifications
chapter. You should become thoroughly familiar with this information
before you operate your vehicle.
Normal characteristics
On some 4WD models, the initial shift from two-wheel drive to 4x4 while
the vehicle is moving can cause some momentary clunk and ratcheting
sounds. This is the front drivetrain coming up to speed and the
automatic locking hubs engaging and is not cause for concern.
Sand
When driving over sand, try to keep all four wheels on the most solid
area of the trail. Avoid reducing the tire pressures but shift to a lower
gear and drive steadily through the terrain. Apply the accelerator slowly
and avoid spinning the wheels.
If you must reduce the tire pressure for whatever reason in sand, make
sure you re-inflate the tires as soon as possible.
Avoid excessive speed because vehicle momentum can work against you
and cause the vehicle to become stuck to the point that assistance may
be required from another vehicle. Remember, you may be able to back
out the way you came if you proceed with caution.
Mud and water
If you must drive through high
water, drive slowly. Traction or
brake capability may be limited.
When driving through water,
determine the depth; avoid water
higher than the bottom of the hubs
(if possible) and proceed slowly. If
the ignition system gets wet, the
vehicle may stall.
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SNOWPLOWING
Ford recommends that the Super Duty F-Series used for snow removal
include the Snow Plow Package Option.
Installing the snowplow
Weight limits and guidelines for selecting and installing the snowplow can
be found in theFord Truck Body Builders Layout Book, Snowplow
section, found at www.fleet.ford.com/truckbbas. A typical installation
affects the following:
•Certification to government safety laws such as occupant protection
and air bag deployment, braking, and lighting. Look for anAlterer’s
Labelon the vehicle from the snowplow installer certifying that the
installation meets all applicable Federal Motor Vehicle Safety
Standards (FMVSS).
•The Total Accessory Reserve Capacity (TARC) is shown on the lower
right side of the vehicle’s Safety Certification Label. This applies to
Ford-completed vehicles of 10,000 lb. GVWR or less. This is the
weight of permanently-attached auxiliary equipment, such as
snowplow frame-mounting hardware, that can be added to the vehicle
and satisfy Ford compliance certification to FMVSS. Exceeding this
weight may require the auxiliary equipment installer additional safety
certification responsibility. The Front Accessory Reserve Capacity
(FARC) is added for customer convenience.
•Rear ballast weight behind the rear axle may be required to prevent
exceeding the FGAWR, and provide front-to-rear weight balance for
proper braking and steering.
•Front wheel toe may require re-adjustment to prevent premature
uneven tire wear. Specifications are found in the FordWorkshop
Manual.
•Headlight aim may require re-adjustment.
•The tire air pressures recommended for general driving are found on
the vehicle’s Safety Certification Label. The maximum cold inflation
pressure for the tire and associated load rating is imprinted on the tire
sidewall. Tire air pressure may require re-adjustment within these
pressure limits to accommodate the additional weight of the snowplow
installation.
•Federal and some local regulations require additional exterior lamps
for snowplow-equipped vehicles. Consult your dealer for additional
information.
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