Operating Guide

23
are what you will need to add.
5. At a service station, add the missing pounds of air
pressure to each tire that is under inated.
6. Check all the tires to make sure they have the same
air pressure except in cases in which the front and
rear tires are supposed to have different amounts
of pressure).
If you have been driving your vehicle and think that a
tire is under inated, ll it to the recommended cold
ination pressure indicated on your vehicle’s tire
information placard or certication label. While your
tire may still be slightly under inated due to the extra
pounds of pressure in the warm tire, it is safer to drive
with air pressure that is slightly lower than the vehicle
manufacturer’s recommended cold ination pressure
than to drive with a signicantly under inated tire.
Since this is a temporary x, don’t forget to recheck
and adjust the tire’s pressure when you can obtain a
cold reading.
3.5.6 tIre SIze
To maintain tire safety, purchase new tires that are the
same size as the vehicle’s original tires or another size
recommended by the manufacturer. Look at the tire
information placard, the owner’s manual, or the sidewall
of the tire you are replacing to nd this information. If
you have any doubt about the correct size to choose,
consult with the tire dealer.
3.5.7 tIre tread
The tire tread provides the gripping action and traction
that prevent your vehicle from slipping or sliding,
especially when the road is wet or icy. In general, tires
are not safe and should be replaced when the tread is
worn down to 2/32 of an inch. Tires have built-in tread
wear indicators that let you know when it is time to
replace your tires. These indicators are raised sections
spaced intermittently in the bottom of the tread grooves.
When they appear “even” with the outside of the tread,
it is time to replace your tires. Another method for
checking tread depth is to place a penny in the tread
with Lincoln’s head upside down and facing you. If you
can see the top of Lincoln’s head, you are ready for
new tires.
3.5.8 tIre Balance and wheel alIgnment
To avoid vibration or shaking of the vehicle when a
tire rotates, the tire must be properly balanced. This
balance is achieved by positioning weights on the wheel
to counterbalance heavy spots on the wheel-and-tire
assembly. A wheel alignment adjusts the angles of the
wheels so that they are positioned correctly relative to
the vehicle’s frame. This adjustment maximizes the
life of your tires. These adjustments require special
equipment and should be performed by a qualied
technician.
3.5.9 tIre repaIr
The proper repair of a punctured tire requires a plug
for the hole and a patch for the area inside the tire
that surrounds the puncture hole. Punctures through
the tread can be repaired if they are not too large, but
punctures to the sidewall should not be repaired. Tires
must be removed from the rim to be properly inspected
before being plugged and patched.
3.5.10 tIre fundamentalS
Federal law requires tire manufacturers to place
standardized information on the sidewall of all tires. This
information identies and describes the fundamental
characteristics of the tire and also provides a tire
identication number for safety standard certication
and in case of a recall.
3.5.10.1 InformatIon on paSSenger VehIcle tIreS
P: The “P” indicates the tire is for passenger vehicles.
Next number: This three-digit number gives the width
in millimeters of the tire from sidewall edge to sidewall
edge. In general, the larger the number, the wider the
tire.
Next number: This two-digit number, known as the
aspect ratio, gives the tire’s ratio of height to width.
Tire Safety