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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. Refer to the payload description and graphic in the
Vehicle loading — with and without a trailersection.
2007 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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2. To reinstall the cover, insert the
four plastic tabs on top of the cover
into the corresponding slots, as
shown in the illustration and push
the cover up into the bumper trim.
3. Hold the cover against the bumper trim and reinstall the two
1 4-turn
fasteners by turning them clockwise.
Preparing to tow
Use the proper equipment for towing a trailer and make sure it is
properly attached to your vehicle. See your authorized dealer or a
reliable trailer dealer if you require assistance.
Hitches
Do not use hitches that clamp onto the vehicle’s bumper or attach to the
axle. You must distribute the load in your trailer so that 10%–15% of the
total weight of the trailer is on the tongue.
Weight distributing hitch
When hooking up a trailer using a load equalizing hitch, always use the
following procedure:
1. Park the unloaded vehicle on a level surface. With the ignition in the
ON position and all doors closed, allow the vehicle to stand (without
passengers) for several minutes so that it can level.
2. Turn the air suspension (if equipped) control to OFF.
3. Measure the height of a reference point on the front and rear bumpers
at the center of the vehicle.
4. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within a
1 2” (13 mm) of the reference point.
After proper adjustment, the rear bumper should be no higher than in
Step 3.
5. Turn the air suspension (if equipped) control to ON.
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.
2007 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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•Wheels out of alignment
•Loose or worn suspension components
Variable assist steering
Your vehicle is equipped with variable assist power steering. At low
engine RPM, steering assist will adjust to reduce efforts and improve low
speed maneuverability. At high engine RPM, the assist will adjust to
improve steering feel at high speeds.
If the amount of effort required to steer your vehicle changes while
driving at a constant engine RPM, have the power steering system
checked by your authorized dealer.
AIR SUSPENSION SYSTEM
The air suspension system is designed to improve ride, handling and
general vehicle performance during:
•Certain road conditions
•Steering maneuvers
•Braking
•Acceleration
This system keeps the rear of your vehicle at a constant level by
automatically adding air or releasing air from the springs. If you exceed
the load limit, the rear air suspension may not operate. The air
suspension system will stay active for 40 minutes after the ignition is
turned off to accommodate any load changes. (The air compressor may
run when the vehicle is off; this is normal.)
The air suspension system can be enabled or disabled through the
message center. Refer toMessage centerin theDriver Controlschapter.
If the system is off, the rear air suspension will not operate and will not
raise (pump) or lower (vent) while the vehicle is not moving. However, if
the system determines that the vehicle is low or high and needs to make
a height adjustment while driving at speeds above 15 mph (24 km/h), the
system will pump or vent as required. Normal vehicle operation does not
require any action by the driver.
On vehicles equipped with air suspension, turn the air
suspension and the ignition switch off prior to jacking, hoisting
or towing your vehicle.
2007 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
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