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GENERALINFORMATIONAND
MAlNTENANdE 1-31
When rotating "unidirectional tires," make sure
that they always roll in the same direction. This
means that a tire used on the left side of the vehicle
must not be switched to the right side and vice-versa.
Such tires should only be rotated front-to-rear or
rear-to-front, while always remaining on the same
side of the vehicle. These tires are marked on the
sidewall as to the direction of rotation; observe the
marks when reinstalling the tire(s).
Some styled or "mag" wheels may have different
offsets front to rear. In these cases, the rear wheels
must not be used up front and vice-versa. Further-
more, if these wheels are equipped with unidirectional
tires, they cannot be rotated unless the tire is re-
mounted for the proper direction of rotation.
*The compact or space-saver spare is
strictly for emergency use. it must never be
included in the tire rotation or placed on the
vehicle for everyday use.
check the installed tire for any sign of interference
with the body or suspension while the vehicle is stop-
ping, turning sharply or heavily loaded.
Snow Tires
Good radial tires can produce a big advantage in
slippery weather, but in snow, a street radial tire does
not have sufficient tread to provide traction and con-
trol. The small grooves of a street tire quickly pack
with snow and the tire behaves like a billiard ball on a
marble floor, The more open, chunky tread of a snow
tire will self-clean as the tire turns, providing much
better grip on snowy surfaces.
To satisfy municipalities requiring snow tires dur-
ing weather emergencies, most snow tires carry either
an M + S designation after the tire size stamped on
the sidewall, or the designation "all-season." In gen-
eral, no change in tire size is necessary when buying
snow tires.
Most manufacturers
stronqlv recommend the use
styled wheels, see if inexpensive steel
wheels are available, Although the look of
the vehicle will change, the expensive
wheels will be protected from salt, curb hits
and pothole damage.
TIRESTORAGE
If they are mounted on wheels, store the tires at
proper inflation pressure. All tires should be kept in a
cool, dry place. If they are stored in the garage or
basement, do not let them stand on a concrete floor;
set them on strips of wood, a mat or a large stack of
newspaper. Keeping them away from direct moisture
is of paramount importance. Tires should not be
stored upright, but in a flat position.
INFLATION & INSPECTION
b See Figures 140 thru 147
TIRE DESIGN
p See Figure 139
for maximum satisfaction, tires should be used in
sets of four. Mixing of different types (radial, bias-
belted, fiberglass belted) must be avoided. In most
cases, the vehicle manufacturer has designated a
type of tire on which the vehicle will perform best.
Your first choice when replacing tires should be to
use the same type of tire that the manufacturer rec-
ommends.
When radial tires are used, tire sizes and wheel di-
ameters should be selected to maintain ground clear-
ante and tire load caoacitv eauivalent to the oriainal
specified tire. Radial tiresshould always be used in
sets of four.
of 4 snow tires on their \ lehicies for reasons of stabil-
ity. If snow tires are fitter 1 only to the drive wheels, the
opposite end of the vehil cle may become very unsta-
ble when braking or turn ring on slippery surfaces.
This instability can lead to unpleasant endings if the
A*:,,"- r-..l, ^_.. ..& ^_^^, &I.
UIIVU MII I LUUII~~MLL
iue slide in time.
Note that snow tires, whether 2 or 4, will affect ve-
hicle handling in all non-snow situations. The stiffer,
heavier snow tires will noticeably change the turning
and braking characteristics of the vehicle. Once the
snow tires are installed, you must re-learn the behav-
ior of the vehicle and drive accordingly.
*Consider buying extra wheels on which to
mount the snow tires. Once done, the "snow
iheeis" can be installed and removed as
needed. This eliminates the potential
dam-
age to tires or wheels from seasonal removal
and installation. Even if your vehicle has
lb
The importance of proper tire inflation cannot be
overemphasized.
A tire employs air as part of its
structure. It is designed around the supporting
strength of the air at a specified pressure. For this
reason, improper inflation drastically reduces the
tire's ability to perform as intended. A tire will lose
some air in day-to-day use; having to add a few
pounds of air periodically is not necessarily a sign of
a leaking tire.
Two items should be a permanent fixture in every
glove compartment: an accurate tire pressure gauge
and a tread depth gauge. Check the tire pressure (in-
eluding the spare) regularly with a pocket type gauge.
Too often, the gauge on the end of the air hose at
vnr rr corner narane is not accurate because it suffers
~rs check tire oressure when the
Radial tires should never be used on only the
XI I._.
'-' --"'"' J s
too much abuse. Alwa!
tires are cold, as pressure increases with tempera-
ture. If you must move the vehicle to check the tire
front axle.
When selecting tires, pay attention to the original
size as marked on the tire. Most tires are described
using an industry size code sometimes referred to as
P-Metric. This allows the exact identification of the
tire specifications, regardless of the manufacturer. If
selecting a different tire size or brand, remember to
METRIC TIRE SIZES
(MILLIMETERS)
145
CDNStRUCtlDN
l-6-E
R - RADIAL
D
WA9
Fig. 139 P-Metric tire coding
Fig. 140 Tires should be checked frequently
I
I
Fig. 141 Tires with deep cuts, or cuts which
for any sion of auncture or damaoe
buioe, should be replaced immediately
l
DRIVE WHEEL HEAW
ACCELERATION
l
OVERINFLATION
*LACK OF ROTATION
Fig. 142 Examples of inflation-related tire
RADIAL
TIRE
fig. 143 Radial tires have a characteristic
sidewall bulge; don't try to measure pres-
sure by looking at the tire. Use a quality air
pressure gauge
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