Chevrolet Spark Owners Manual: Tire Designations
Tire Size
The following is an example of a typical passenger vehicle tire size.
(1) 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.
(2) Tire Width: The three-digit number indicates the tire section width in millimeters from sidewall to sidewall.
(3) Aspect Ratio: A two-digit number that indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 60, as shown in item 3 of the illustration, it would mean that the tire's sidewall is 60 percent as high as it is wide.
(4) 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.
(5) Rim Diameter: Diameter of the wheel in inches.
(6) Service Description: These characters represent the load index and speed rating of the tire. The load index represents the load carrying capacity a tire is certified to carry. The speed rating is the maximum speed a tire is certified to carry a load.
Tire Sidewall Labeling
Useful information about a tire is molded into its sidewall. The examples show
a typical passenger tire sidewall.
Passenger (P-Metric) Tire Example
(1) Tire Size: The tire size is a combinatio ...
Tire Terminology and Definitions
Air Pressure: The amount of air inside the tire pressing outward on each square
inch of the tire. Air pressure is expressed in kPa (kilopascal) or psi (pounds per
square inch).
Accessory Weight: ...
Other materials:
Tire Pressure Monitor
This vehicle may have a Tire Pressure Monitor System (TPMS).
The low tire pressure warning light
alerts to a significant loss in pressure of one of the vehicle's tires. If the warning
light comes on, stop as soon as possible and inflate the tires to the recommended
pressure shown on the T ...
Where to Put the Restraint
According to accident statistics, children and infants are safer when properly
restrained in a child restraint system or infant restraint system secured in a rear
seating position.
Whenever possible, children aged 12 and under should be secured in a rear seating
position.
Never put a rear-fa ...
Older Children
Older children who have outgrown booster seats should wear the vehicle safety
belts.
The manufacturer instructions that come with the booster seat state the weight
and height limitations for that booster. Use a booster seat with a lap-shoulder
belt until the child passes the fit test belo ...
