This standard specifies tire dimensions and laboratory test requirements for bead unseating resistance@ strength@ endurance@ and high speed performance; defines tire load ratings; and specifies labeling requirements for passenger car tires. Application. This standard applies to new pneumatic radial tires for use on passenger cars manufactured before 1975@ new pneumatic bias ply tires@ Ttype spare tires@ ST@ FI@ and 8?C12 rim diameter and below tires for use on passenger cars manufactured after 1948. However@ it does not apply to any tire that has been so altered so as to render impossible its use@ or its repair for use@ as motor vehicle equipment.