Tire Labeling; Tire Size Designation, Load-Bearing Capacity And Speed Rating - Mercedes-Benz GLA 250 2019 Operator's Manual

All about wheels and tires
320
tion, or excessive loading, either separately
or in combination, can cause excessive heat
build-up and possible tire failure.
The temperature grades are A (the highest), B,
and C, representing the tire's resistance to the
generation of heat and its ability to dissipate
heat when tested under controlled conditions
on a specified indoor laboratory test wheel.
Sustained high temperature can cause the
material of the tire to degenerate and reduce
tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds
to a level of performance which all passenger
car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B
and A represent higher levels of performance
on the laboratory test wheel than the minimum
required by law.

Tire labeling

Overview
: Uniform Tire Quality Grading Standards
( page 323)
Y
Department of Transportation, Tire Identifi-
;
cation Number (
Maximum load rating (
=
Maximum tire pressures (
?
Manufacturer
A
B Tire material (
C Tire size designation, load-bearing capacity
and speed rating (
page 322)
Y
page 322)
Y
page 310)
Y
page 323)
Y
page 320)
Y
Load index ( page 322)
D
Y
E Tire name
The markings described above are on the tire
in addition to the tire name (sales designation)
and the manufacturer's name.
i
Tire data is vehicle-specific and may devi-
ate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
G
WARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed
could lead to tire damage or the tire burst-
ing. There is a risk of accident.
Therefore, only use tire types and sizes
approved for your vehicle model. Observe
the tire load rating and speed rating
required for your vehicle.
Tire width
:
Nominal aspect ratio in %
;
= Tire code
Rim diameter
?
Load bearing index
A
Speed rating
B
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size descrip-
tion (as shown above): these are passenger
vehicle tires according to European manufac-
turing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S. man-
ufacturing standards.