•Narrower — to provide greater
maneuverability in tight spaces,
particularly in off-road use.
As a result of the above dimensional
differences, SUV’s and trucks often
will have a higher center of gravity
and a greater difference in center of
gravity between the loaded and
unloaded condition.
These differences that make your
vehicle so versatile also make it
handle differently than an ordinary
passenger car.
INFORMATION ABOUT UNIFORM TIRE QUALITY GRADING
New vehicles are fitted with tires
that have a rating on them called
Tire Quality Grades. The Quality
grades can be found where
applicable on the tire sidewall
between tread shoulder and
maximum section width. For
example:
•Treadwear 200 Traction AA Temperature A
These Tire Quality Grades are determined by standards that the United
States Department of Transportation has set.
Tire Quality Grades apply to new pneumatic tires for use on passenger
cars. They do not apply to deep tread, winter-type snow tires,
space-saver or temporary use spare tires, tires with nominal rim
diameters of 10 to 12 inches or limited production tires as defined in
Title 49 Code of Federal Regulations Part 575.104(c)(2).
U.S. Department of Transportation-Tire quality grades:The U.S.
Department of Transportation requires Ford Motor Company to give you
the following information about tire grades exactly as the government
has written it.
2008 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
197
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
•Tow a trailer
•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
•Winter weather driving capability
•Wet weather driving capability
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
2008 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
276
