Operator`s manual
1213 1200.01 
24 
weight or accessory weight, including heavy duty brakes, ride levelers, roof rack, heavy duty 
battery, and special trim. 
Radial ply tire 
A pneumatic tire in which the ply cords that extend to the beads are laid at substantially 90 
degrees to the centerline of the tread. 
Recommended inflation pressure 
This is the inflation pressure provided by the vehicle manufacturer on the Tire Information label 
and on the Certification / VIN tag. 
Reinforced tire 
A tire designed to operate at higher loads and at higher inflation pressures than the 
corresponding standard tire. 
Rim 
A metal support for a tire or a tire and tube assembly upon which the tire beads are seated. 
Rim diameter 
This means the nominal diameter of the bead seat. 
Rim size designation 
This means the rim diameter and width. 
Rim type designation 
This means the industry of manufacturer’s designation for a rim by style or code. 
Rim width 
This means the nominal distance between rim flanges. 
Section width 
The linear distance between the exteriors of the sidewalls of an inflated tire, excluding 
elevations due to labeling, decoration, or protective bands.   
Sidewall 
That portion of a tire between the tread and bead. 
Sidewall separation 
The parting of the rubber compound from the cord material in the sidewall. 
Special Trailer (ST) tire 
The "ST" is an indication the tire is for trailer use only. 
Test rim 
The rim on which a tire is fitted for testing, and may be any rim listed as appropriate for use 
with that tire. 
Tread 
That portion of a tire that comes into contact with the road. 
Tread rib 
A tread section running circumferentially around a tire. 
Tread separation 
Pulling away of the tread from the tire carcass. 
Treadwear indicators (TWI) 
The projections within the principal grooves designed to give a visual indication of the degrees 










