Chapter 36 Wheels and Tire Theory
casing plies - ANS-A network of cords that give the tire shape and strength.
cornering force - ANS-The force between the tread and the road surface as a vehicle turns.
deep dish wheel - ANS-negative offset on a wheel which gives it a deep dish appearance.
Deep dish refers to the side of the wheel that is farthest from the drop center.
drop center - ANS-A wheel design with part of the center section of the wheel a smaller
diameter than the rest. It is used for mounting and demounting the tire.
EH2 rim - ANS-The specialized rim design that is used with some run-flat tires.
extended mobility technology - ANS-Tires with thick sidewalls that allow the tire to be driven on
even when it has no air pressure.
flat seat with washer - ANS-A type of lug nut that is flat where it bolts to the wheel and has a
washer affixed that allows it to turn independent of the hex part of the lug nut.
flat seat without washer - ANS-A type of lug nut that is flat where it bolts to the wheel.
lug nuts - ANS-Nuts that secure the wheel onto the wheel studs.
oversteer - ANS-A condition in which the front slip angles are larger than the rear slip angles.
The vehicle is said to be "pushing" in the corners.
pitch circle diameter - ANS-The diameter of the imaginary circle drawn through the center of the
wheel bold holes.
ply rating - ANS-A rating system that denotes the number of belt layers that make up the tire
carcass. In radial tires, this denotes the relative strength of the plies, not the actual number of
plies.
radial tire - ANS-A tire with two or more layers of casing plies and cord loops running radially
from bead to bead.
rim flanges - ANS-The outside edge of the wheel that helps keep the tire from popping off the
wheel.
casing plies - ANS-A network of cords that give the tire shape and strength.
cornering force - ANS-The force between the tread and the road surface as a vehicle turns.
deep dish wheel - ANS-negative offset on a wheel which gives it a deep dish appearance.
Deep dish refers to the side of the wheel that is farthest from the drop center.
drop center - ANS-A wheel design with part of the center section of the wheel a smaller
diameter than the rest. It is used for mounting and demounting the tire.
EH2 rim - ANS-The specialized rim design that is used with some run-flat tires.
extended mobility technology - ANS-Tires with thick sidewalls that allow the tire to be driven on
even when it has no air pressure.
flat seat with washer - ANS-A type of lug nut that is flat where it bolts to the wheel and has a
washer affixed that allows it to turn independent of the hex part of the lug nut.
flat seat without washer - ANS-A type of lug nut that is flat where it bolts to the wheel.
lug nuts - ANS-Nuts that secure the wheel onto the wheel studs.
oversteer - ANS-A condition in which the front slip angles are larger than the rear slip angles.
The vehicle is said to be "pushing" in the corners.
pitch circle diameter - ANS-The diameter of the imaginary circle drawn through the center of the
wheel bold holes.
ply rating - ANS-A rating system that denotes the number of belt layers that make up the tire
carcass. In radial tires, this denotes the relative strength of the plies, not the actual number of
plies.
radial tire - ANS-A tire with two or more layers of casing plies and cord loops running radially
from bead to bead.
rim flanges - ANS-The outside edge of the wheel that helps keep the tire from popping off the
wheel.
