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:
Replacing Safety Belt System Parts after a Crash
Warning
A crash can damage the safety belt system in the vehicle.
A damaged safety belt system may not properly protect the person using it, resulting
in serious injury or even death in a crash. To help make sure the safety belt systems
are working properly after a crash, have them inspected a ...
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal collisions, even belted occupants
can contact the steering wheel or the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside of the vehicle.
Airbags supplement the protection provided by safety belts ...
Lower Anchors and Tethers for Children (LATCH System)
The LATCH system secures a child restraint during driving or in a crash.
LATCH attachments on the child restraint are used to attach the child restraint
to the anchors in the vehicle. The LATCH system is designed to make installation
of a child restraint easier.
In order to use the LATCH syste ...