th ese are ins ta lled on th e ve hicle, but does not
include passengers or luggage.
Maximum tire load: th e maximum tire load is
th e maximum permissible we ight in kilog ra ms or
lbs fo r whi ch a tire is appr ove d.
Maximum permissible tire pressure: maxi‐
mum permissible tire pressure fo r one tire.
Maximum load on one tire: maximum load on
one tire. This is calculated by dividing th e maxi‐
mum axle load of one axle by two.
PSI (pounds per square in ch ): st andard unit of
measurement fo r tire pressu re .
Aspect ra tio: ra tio between tire height and tire
width in pe rc ent.
Ti re pressure: pressure inside th e tire applying
an outward fo rc e to eve ry square inch of th e tire.
The tire pressure is specified in pounds per
square inch (psi), in kilopascals (kPa) or in bar.
The tire pressure should only be cor re cted when
th e tires are cold.
Cold tire pressure: th e tires are cold when th e
ve hicle has been par ke d fo r at lea st 3 hou rs without direct sunlight on th e tires or th e ve hicle
has been driven fo r less th an 1 mile (1.6 km).
Ti re contact sur fa ce: th e part of th e tire th at
comes into con ta ct wi th th e ro ad.
Ti re bead: th e purpose of th e tire bead is to
ensure th at th e tire sits securely on th e wheel
ri m. There are se ve ra l wire cores in th e tire bead
to pr eve nt th e t ir
e from ch anging length on th e
wheel ri m.
Side wa ll: th e part of th e tire between th e tread
and th e tire bead.
We ight of optional equipment: th e combined
we ight of th e optional equipment we ighing more
th an th e re placed st andard parts and more th an
5 lbs (2.3 kg ). This optional equipment, such as
high-per fo rm ance brakes, le ve l control sy st em, a
ro of luggage ra ck or high-per fo rm ance bat te ri es,
is not included in th e curb we ight and th e we ight
of th e accessories.
TIN (Tire Identification Nu mber): a uni qu e
identification number which can be used by a
tire manufactu re r to identify tires, fo r ex ample,
in a product re call, and th us identify th e pur‐
ch asers. The TIN is made up of th e manufactur‐ er's identity code, tire size, tire type code and
th e manufacturing date.
Load-bearing index: th e load-bearing index is a
code th at con ta ins th e maximum load-bearing
capacity of a tire.
Tr action: traction is th e grip re sulting from fric‐
tion between th e tires and th e ro ad sur fa ce.
We ar indicator: nar row bars (tread we ar bars)
th at are distributed ove r th e tire con ta ct su rf ace.
If th e tire tread is le ve l with th e bars, th e we ar
limit of 1/ 16 in (1.6 mm) has been re ached.
Distribution of ve hicle occupants: distribution
of ve hicle occupants ov er designated seat posi‐
t ions in a ve hicle.
Maximum permissible pa yl oad we ight: nomi‐
nal load and luggage load plus 15 0 lb (68 kg )
multiplied by th e number of seats in th e ve hicle.432
Wheels and tires