Tire and Loading Glossaries
General Wheel and Tire Terms
Accessory WeightThe combined weight (in excess of those items replaced) of items available as factory
installed equipment.BeadThe inner edge of a tire that is shaped to fit to the rim and form an air tight seal. The
bead is constructed of steel wires which are wrapped, or reinforced, by the ply cords.Cold Tire PressureThe air pressure in a tire that has been standing in excess of three hours, or driven for less than one mile.Curb WeightThe weight of a standard vehicle, including any optional equipment fitted, and with the
correct
fluid levels.
Gross Vehicle WeightThe maximum permissible weight of a vehicle with driver, passengers, load, luggage, and
equipment.kPa (kilo pascal)A metric unit used to measure pressure. One kilo pascal equals approximately 0.145 psi.Maximum Inflation
Pressure
The maximum pressure to which the tire should be inflated. This pressure is given on the
tire side wall in psi (lbf/in2).
CAUTION: This pressure marked on the tire is the maximum allowed by the tire
manufacturer. It is not the pressure Tesla recommends using for Model 3.
Maximum Loaded
Vehicle WeightThe sum of curb weight, accessory weight, vehicle capacity weight, and production options weight.Production Options
WeightThe combined weight of options installed which weigh in excess of 3 lb (1.4 kg) more
than the standard items that they replaced, and are not already considered in curb or
accessory weights.PSI (lbf/in2)Pounds per square inch (the unit used to measure tire pressure).Recommended Tire
Inflation Pressure
Tire inflation pressure, established by Tesla, which is based on the type of tires that are
mounted on the vehicle at the factory. This information can be found on the Tire and
Loading Information label located on the door pillar.RimThe metal support for a tire, or tire and tube, upon which the tire beads are seated.Vehicle Capacity
WeightThe number of seats multiplied by 150 lbs (68 kg) plus the rated amount of load/luggage.
Load Carrying Definitions
Normal occupant weight68 kilograms (150 lbs) times the number of occupants specified in the second column
of the tables for calculating load limits (see
Vehicle Loading on page 180).
Occupant distributionDistribution of occupants in a vehicle.Passenger car tireA tire intended for use on passenger cars, multipurpose passenger vehicles, and trucks, that have a gross vehicle weight rating (GVWR) of 10,000 lbs (4536 kg) or less.Rim diameterNominal diameter of the bead seat.Rim size designationRim diameter and width.Rim type designationThe manufacturing industry
Vehicle normal load on the
tireLoad on an individual tire that is determined by distributing to each axle its share of
the curb weight, accessory weight, and normal occupant weight and dividing by two.
Pneumatic Radial Tire Definitions
Bead separationA breakdown of the bond between components in the bead.Bias ply tireA pneumatic tire in which the ply cords that extend to the beads are laid at alternate angles
substantially less than 90 degrees to the center line of the tread.CarcassThe tire structure, except tread and sidewall rubber which, that when inflated, bears the load.ChunkingThe breaking away of pieces of the tread or sidewall.CordThe strands forming the plies in the tire.Cord separationThe parting of cords from adjacent rubber compounds.CrackingAny parting within the tread, sidewall, or inner liner of the tire extending to cord material.Extra load tireA tire designed to operate at higher loads and higher inflation pressure than the
corresponding standard tire.GrooveThe space between two adjacent tread ribs.Inner linerThe layer(s) forming the inside surface of a tubeless tire that contains the inflating medium
within the tire.Inner liner
separationThe parting of the inner liner from cord material in the carcass.Load ratingThe maximum load that a tire is rated to carry for a given inflation pressure.Maximum load
ratingThe load rating for a tire at the maximum permissible inflation pressure for that tire.Measuring rimThe rim on which a tire is fitted for physical dimension requirements.Open spliceAny parting at any junction of tread, sidewall, or inner liner that extends to the cord material.Outer diameterThe overall diameter of an inflated new tire.Overall widthThe linear distance between the exteriors of the sidewalls of an inflated tire, including
elevations due to labeling, decorations, or protective bands or ribs.PlyA layer of rubber-coated parallel cords.Ply separationA parting of rubber compound between adjacent plies.Pneumatic tireA mechanical device made of rubber, chemicals, fabric and steel or other materials, that,
when mounted on an automotive wheel, provides the traction and contains the gas or
fluid
that sustains the load.
Radial ply tireA pneumatic tire in which the ply cords that extend to the beads are laid at substantially 90
degrees to the center line of the tread.Reinforced tireA tire designed to operate at higher loads and at higher inflation pressures than the
corresponding standard tire.Section widthThe linear distance between the exteriors of the sidewalls of an inflated tire, excluding
elevations due to labeling, decoration, or protective bands.SidewallThe portion of a tire between the tread and bead.Sidewall separationThe parting of the rubber compound from the cord material in the sidewall.
Wheels and Tires
191Specifications
