440 6-1. Specifications
Tire related termMeaning
Overall widthThe linear distance between the exteriors of
the sidewalls of an inflated tire, including eleva-
tions due to labeling, decorations, or protective
bands or ribs
Passenger car tireA tire intended for use on passenger cars, mul-
tipurpose passenger vehicles, and trucks, that
have a gross vehicle weight rating (GVWR) of
10,000 lb. or less.
Ply A layer of rubber-coated parallel cords
Ply separationA parting of rubber compound between adja-
cent plies
Pneumatic tireA mechanical device made of rubber, chemi-
cals, fabric and steel or other materials, that,
when mounted on an automotive wheel, pro-
vides 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 centerline of the tread
Reinforced tireA tire designed to operate at higher loads and
at higher inflation pressures than the corre-
sponding standard tire
Section widthThe linear distance between the exteriors of
the sidewalls of an inflated tire, excluding ele-
vations due to labeling, decoration, or protec-
tive bands
SidewallThat portion of a tire between the tread and
bead
Sidewall separationThe parting of the rubber compound from the
cord material in the sidewall