Tires and wheels
>> Operation
197
General:
Depending on the design standards used, the
tire size molded into the sidewall may have no
letter or a letter preceding the tire size des
ignation.
No letter preceding the size designation
(as illustrated above): Passenger car tire
based on European design standards.
Letter "P" preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter "LT" preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter "T" preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.
Tire width
Tire width1
(page 196) indicates the
nominal tire width in mm.Aspect ratio
Aspect ratio2
(page 196) is the dimen
sional relationship between tire section
height and section width and is expressed in
percentage. The aspect ratio is arrived at by
dividing section height by section width.
Tire code
Tire code3 (
page 196) indicates the tire
construction type. The "R" stands for radial
tire type. Letter "D" means diagonal or bias
ply construction; letter "B" means belted
bias ply construction.
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a "ZR" in the size
designation (for example: 245/40 ZR 18).
For additional information, see "Tire speed
rating" (
page 198)
.
Rim diameter
Rim diameter4 (
page 196) is the diameter
of the bead seat, not the diameter of the rim
edge. Rim diameter is indicated in inches (in).Tire load rating
Tire load rating5 (
page 196) is a numeri
cal code associated with the maximum load a
tire can support.
For example, a load rating of 91 corresponds
to a maximum load of 1 356 lbs (615 kg) the
tire is designed to support.
See also "Maximum tire load" (
page 201)
where the maximum load associated with the
load index is indicated in kilograms and lbs.
G
Warning!
The tire load rating must always be at
least half of the GAWR (
page 205) of
your vehicle. Otherwise, tire failure may
result and cause an accident and/or seri
ous personal injury to you or others.
Always replace rims and tires with the
same designation, manufacturer and type
as shown on the original part.
