1993 PONTIAC GRAND-PRIX tires

Inflation-Tire Pressure
The Tire-Loading Information label
which is on the inside of the trunk lid
shows the correct inflation pressures for
your tires, when they’re cold. “Cold”
means your vehicle has been sitting for
at least three hours or driven
no more
than a mile. Don’t let anyone
tell you th
underinflation
or overinflati
all right. It’s not.
If your tires d
have enough air (underinflation
Too much heat
If your tires have too much air
When to Check:
Check your tires once a month or more.
Don’t forget your compact spare tire. It
should be at
60 psi (420 ItPa).
How to Check:
Use a good quality pocket-type gage to
check tire pressure. Simply loolting at
the tires will not tell you the pressure,
especially if you have radial tires-
which may
look properly inflated even if
they’re underinflated.
If your tires have valve caps, be sure to
put them back on. They help prevent
leaks by keeping out dirt
and moisture.
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§ervice & Appearance Care
.a.
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Tire Inspection and Rotation
To make your tires last longer, have
them inspected and rotated at the
mileages recommended in the
Maintenance Schedule. See the
Index
under Scheduled Maintenance
Services.
Use this rotation pattern.
If you don't have P245/50ZR16 size
tires, use the rotation pattern shown
above for your size tires.
256
If you have P245/510ZR16 size tires,
they must roll
in a certain 'direction for
the best overall performance. The
direction is shown
by an arrow on both
sidewalls. Because these tirles are
directional, they should be rotated
as
shown in the example above. These
tires should only be moved
from front
to rear and rear to front
on the same
side
of the vehicle.
After the tires have been rotated, adjust
the front and rear inflation pressure as
shown
on the Tire-Loading Information
label. Make certain that
all wheel nuts
are properly tightened. See the Index
under Wheel Nut Torque.
Rust or dirt on a wheel, or on
ri the parts to which it is
fastened, can make wheel nuts
become loose after a time. The
wheel could come off and cause an
accident. When you change a
wheel, remove any rust or dirt from
places where the wheel attaches to
the vehicle. In an emergency,
you
can use a cloth or a paper towel to
do this; but be sure to use a scraper
or wire brush later,
if you need to,
to get all the rust or dirt off. (See
the
Index under Changing a Flat
Tire.)
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When It’s Time for New Tires
One way to tell when it’s time for new
tires is to check the treadwear
indicators, which will appear when your
tires have only
2/32 inch (1.6 mm) or
less
of tread remaining.
You need a new tire if:
You can see the indicators at three
You can see cord or fabric showing
The tread or sidewall is cracked, cut
places
around the tire.
through the tire’s rubber.
or snagged deep enough to show cord
or fabric.
The tire has a bump, bulge or split.
The tire has a puncture, cut, or other
damage that can’t
be repaired well
because
of the size or location of the
damage.
Buying New Tires
To find out what kind and size of tires
you need, look at the Tire-Loading
Information label. The tires installed on
your vehicle when it was new had a Tire
Performance Criteria Specification
(TPC Spec) number on each tire’s
sidewall. When
you get new tires, get
ones with that same
TPC Spec number.
That way, your vehicle will continue to
have tires that are designed to give
proper endurance, handling, speed
rating, traction, ride and other things
during normal service on your vehicle.
If your tires have an all-season tread
design, the
TPC number will be
followed by a
“MS” (for mud and
snow). If
you ever replace your tires with those
not having a
TPC Spec number, make
sure they are the same size, load range,
speed rating and construction type
(bias, bias-belted or radial) as your
original tires.
‘1 Mixing tires could cause you
A to lose control while driving.
If you mix tires
of different sizes or
types (radial and bias-belted tires),
the vehicle may not handle
properly, and you could have a
crash. Be sure to use the same size
and type tires on all wheels. It’s all
right to drive with your compact
spare, though. It was developed for
limited use on vour vehicle.
r
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Service &.Appearance Care
Grading
The following information relates to the
system developed by the United States
National Highway Traffic Safety
Administration which grades tires by
treadwear, traction and temperature
performance. (This applies only to
vehicles sold in the United States.)
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 a half (1%)
times as well on the government course
as a tire graded
100. The relative
performance
of tires depends upon the actual conditions
of their use, however,
and may depart significantly from the
norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.
Traction-A, B, C
The traction grades, from highest to
lowest are:
A, B, and C. They 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.
Warning: The traction grade assigned
to this tire is based on braking (straight-
ahead) traction tests and does not
include cornering (turning) traction.
Temperature-A, B, C
The temperature grades are A (the
highest),
€3, 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. Sustained high
temperature can cause the material of
the tire to degenerate and reduce tire
life, and excessive temperature can lead
to sudden tire failure. The grade
C
corresponds to a level of performance
which all passenger car tires must meet
under the Federal Motor Vehicle Safety
Standard
No. 109. Grades B and A
represent higher levels of performance
on the laboratory test wheel than the
minimum required by law.
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Warning: The temperature grade for
this tire is established
for a tire that is
properly inflated and not overloaded.
Excessive speed, underinflation, or
excessive loading, either separately or
in combination, can cause heat buildup
and possible tire failure.
Those grades are molded
on the
sidewalls of passenger car tires.
While the tires available as standard or
optional equipment
on General Motors
vehicles may vary with respect to these
grades, all such tires meet General
Motors performance standards and have
been approved for use on General
Motors vehicles.
All passenger type
(P Metric) tires must conform to
Federal safety requirements in addition
to these grades.
Wheel AIignrnenf and
Tire Balance
The wheels on your vehicle were aligned
and balanced carefully at the factory to
give you the longest tire life and best
overall performance.
In most cases, you will not need to have
your wheels aligned again. However, if
you notice unusual tire wear or your
vehicle pulling one way
or the other, the
alignment may need to be reset. If
you
notice your vehicle vibrating when
driving
on a smooth road, your wheels
may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked
or badly rusted.
If wheel nuts keep
coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If
the wheel leaks air out, replace it
(except some aluminum wheels, which
can sometimes be repaired). See your
Pontiac dealer if any
of these conditions
exist.
Your dealer will how the kind
~f wheel
you need.
Each new wheel should
have the same
load carrying capacity, diameter, width,
offset, and be mounted the same way as
the one it replaces.
If
you need to replace any of your
wheels, wheel bolts, or wheel nuts,
replace them only with
new GM original
equipment parts. This
way, you will be
sure
to have the right wheel, wheel
bolts, and wheel nuts
for your Pontiac
model.
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Service 4S Appearance Care
Used Replacement Wheels Tire Chains
Using the wrong replacement I
1‘ I wheels, wheel bolts, or wheel
nuts on your vehicle can be
dangerous. It could affect the
braking md handling of you
vehicle, make your tires lose air and
make you lose control. You could
have a collision in which yau or
others could be injured. Always use
the correct wheel, wheel bolts, and
wheel nuts for replacement.
The wrong wheel can also cause
problems with bearing
life, brake
cooling, speedometer/odometer
calibration, headlight
aim, bumper
height, vehicle ground clearanr
and tire or tire chain clearancc
he body and chassis.
Putting a used wheel on your
1 b vehicle is dangerous, You
can’t how how it’s beerl used or
how rnany miles 8s been driven. It
could fail suddenly and muse an
accident. If you have to replace a
wheel use a new GM original
equipment wheel. I
If your Pontiac has P215/60R16,
P225/60R16 or P245/50ZR16 size
tires, don’t use tire chains; they
can damage your vehicle.
If you have other tires,
use
chains only when you must. I
only SAE Class “S” type chains
that are the proper size for your
tires. Install them on the front til
and tighten them as tightly as
possible with the ends securely
fastened. Drive slowly and
fnlh
the chain manufacturer’s
instructions. If you can hear
t
chains contacting your vehicle,
stop and retighten them.
If the
contact continues, slow
down until
it stops. Driving too fast with
chains on will damage your
vehicle.
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Service & Appearance Care
mu.
Finish Care
Occasional waxing or mild polishing of
your Pontiac may be necessary to
remove residue from the paint finish.
You can get
GM approved cleaning
products from your dealer. (See the
Index under Appearance Care. )
Your Pontiac has a ‘‘basecoat/
clearcoat” paint finish. The clearcoat
gives more depth and gloss
to the
colored basecoat.
Machine compounding or
aggressive polishing
on a
basecoat/clearcoat paint finish may
dull the finish
or leave swirl marks. I
E66
Aluminum Wheels (IF so EQUIPPED)
Your aluminum wheels have a
protective coating similar to the painted
surface of your Pontiac. Don’t use
strong soaps, chemicals, chrome polish,
or other abrasive cleaners on them
because you could damage this coating.
After rinsing thoroughly, a wax may be
applied.
White Sidewall Tires
Your Pontiac dealer has a GM White
Sidewall Tire Cleaner.
You can use a
stiff brush with it.
Weatherstrips
These are places where glass or metal
meets rubber. Silicone grease there will
male them last longer, seal better, and
not squeak. Apply silicone grease with a
clean cloth at least every six months.
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Maintenance Schedule
Section A: Scheduled Maintenance Services t~ont.3
Explanation of Scheduled Maintenance Services
Below are explanations of the services listed in Schedule I
and Schedule 11.
ITEM
NO. SERVICE
1 Engine Oil and Filter Change’:-Always use SG
Energy Conserving I1 oils for proper viscosity. The
“SG” designation may be shown alone or in
combination with others, such as “SG/CC,”
“SG/CD” or
“SF, SG, CC,” etc. To determine the
preferred viscosity for your vehicle’s engine (e.g.,
SAE
5W-30 or SAE 1OW-30) see the Index under
Engine OiZ. If your vehicle is equipped with an
Engine Oil-Change Indicator (EOCI)
, the
indicator will show you when to change oil. See
the
Index under Driver Information Center.
2 Chassis Lubrication-Lubricate the transaxle shift
linkage, parking brake cable guides, underbody
contact points and linkage. Lubricate the front and
rear suspension and steering linkage. The
proper fluids and lubricants to use are listed in Section
D. Make sure whoever services your vehicle uses these. All
parts should be replaced and all necessary repairs done
before you or anyone else drives the vehicle.
ITEM
NO. SERVICE
3 Throttle Body Mounting Bolt Torque (3.1L
Code T engine only)‘x- Check the torque of the
mounting bolts and/or nuts.
Tire and Wheel Rotation and Inspection -For
long wear and maximum tire life, rotate your tires
following the instructions in this manual. See the
Index under Tires, Inspection G. Rotation. Check
the tires for uneven wear or damage.
If you see
irregular or premature wear, check the wheel alignment. Check for damaged wheels also.
4
a The U.S. Environmental Protection Agency has determined that the failure to perform this maintenance item will not nullify the emission warranty or
limit recall liability prior to the completion of vehicle useful life. General Motors, however, urges that all recommended maintenance services be
performed at the indicated intervals and the maintenance be recorded
in Section E: Maintenance Record.
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