Normal Occupant Weight: The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). See Loading Your Vehicle
on page 4-21.
Occupant Distribution
: Designated seating
positions.
Outward Facing Sidewall
: The side of an
asymmetrical tire that has a particular side that
faces outward when mounted on a vehicle.
The side of the tire that contains a whitewall, bears
white lettering, or bears manufacturer, brand,
and/or model name molding that is higher
or deeper than the same moldings on the other
sidewall of the tire.
Passenger (P-Metric) Tire
: A tire used on
passenger cars and some light duty trucks and
multipurpose vehicles.
Recommended Inflation Pressure
: Vehicle
manufacturer’s recommended tire inflation
pressure as shown on the tire placard.
See Inflation - Tire Pressure on page 5-61 and
Loading Your Vehicle on page 4-21.
Radial Ply Tire
: A pneumatic tire in which the ply
cords that extend to the beads are laid at
90 degrees to the centerline of the tread.
Rim
: A metal support for a tire and upon which
the tire beads are seated.
Sidewall
: The portion of a tire between the tread
and the bead.
Speed Rating
: An alphanumeric code assigned to
a tire indicating the maximum speed at which a
tire can operate.
Traction
: The friction between the tire and the
road surface. The amount of grip provided.
Tread
: The portion of a tire that comes into
contact with the road.
Treadwear Indicators
: Narrow bands, sometimes
called wear bars, that show across the tread of
a tire when only 1/16 inch (1.6 mm) of tread
remains. See When It Is Time for New Tires on
page 5-70.
5-60
