Tire Size
The following illustration shows an example of a typical
passenger car tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P as
the first character in the tire size means a passenger
vehicle tire engineered to standards set by the U. S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is 70, as shown in item C of
the illustration, it would mean that the tire’s sidewall
is 70% as high as it is wide.(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The
letter R means radial ply construction; the letter D means
diagonal or bias ply construction; and the letter B means
belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:These characters represent
the load range and the speed rating of a tire. The
load range represents the load carry capacity a tire is
certified to carry. The speed rating is the maximum
speed a tire is certified to carry a load. Speed ratings
range from A to Z.
Tire Terminology and De nitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire’s height to
its width.
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Part D: Recommended Fluids
and Lubricants
Fluids and lubricants identified below by name, part
number or specification may be obtained from your
dealer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets GM Standard
GM6094M and displays the
American Petroleum Institute
Certified for Gasoline Engines
starburst symbol. GM Goodwrench
®
oil meets all the requirements for your
vehicle. To determine the proper
viscosity for your vehicle’s engine,
seeEngine Oil on page 5-13.
Engine Coolant50/50 mixture of clean, drinkable
water (preferably distilled) and good
quality Ethylene Glycol Base Coolant
(GM Part No. U.S. 12378560,
in Canada 993089) and conforming
to GM Specification 1825M or
recycled coolant conforming to
GM Specification 1825M.
SeeEngine Coolant on page 5-21.
Usage Fluid/Lubricant
Hydraulic Brake
SystemDelco Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
Washer SolventGM Optikleen
®Washer Solvent.
Power Steering
SystemDEXRON
®-III Automatic
Transmission Fluid. Look for
“Approved for the H-Specification”
on the label.
Automatic
TransaxleUse only T-IV Automatic
Transmission Fluid (GM Part No.
U.S. 88900925, in Canada
22689186). SeeAutomatic
Transaxle Fluid on page 5-18.
Manual
TransaxleGM Goodwrench
®Synthetic Manual
Transmission Fluid (GM Part No.
U.S. 12346190, in Canada
10953477) or equivalent
SAE 75W-85 GL-4 gear oil.
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