Permissible Gross Vehicle Weight Rating
(GVWR):the gross weight of the vehicle, all pas-
sengers, load and trailer load/noseweight (if
applicable) must not exceed the permissible
gross vehicle weight.
Gross Axle Weight Rating (GAWR): the maxi-
mum permissible weight that can be carried by
one axle (front or rear axle).
To ensure that your vehicle does not exceed the
maximum permissible values (gross vehicle
weight and maximum gross axle weight rating),
have your loaded vehicle (including driver, occu-
pants, cargo, and full trailer load if applicable)
weighed on asuitable vehicle weighbridge.
All about wheelsa nd tires
Uniform Tire Quality Grading Stand-
ards
Overview of Tire Quality Grading Stand-
ards
Uniform Tire Quality Grading Standards are U.S. governments pecifications. Their purpose is to
provide drivers with uniform reliable information
on tire performance data. Tire manufacturers
have to grade tires using three performance fac-
tors: :tread wear grade, ;traction grade and
= temperature grade. These regulations do not
apply to Canada. Nevertheless, all tires sold in
North America are provided with the corre-
sponding quality grading markings on the side-
wall of the tire.
Quality grades can be found, where applicable,
on the tire sidewallb etween tread shoulder and
maximum section width. Example:
RTreadwear grade:
200
RTraction grade:AA
RTemperaturegrade:A
All passenger car tires must conformtot he stat-
utory safety requirements in addition to these
grades.
iThe actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
Treadwear
The treadwear grade is acomparative rating
based on the wear rate of the tire when tested
under controlled conditionsonas pecified U.S.
governmentc ourse. For example, atire graded
150 would wear one and one-half times as well
on the governmentc ourse asatire graded 100.
The relative performance of tires depends upon the actual conditionsoft heir use, however, and
may depart significantly from the norm due to
variations in driving habits, service practices
and differences in road characteristics and cli-
mate.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor-
nering, hydroplaning, or peak traction char-
acteristics.
!Avoid wheelspin. This can lead to damage to
the drive train.
The traction grades –from highest to lowest –
are AA, A, Band C. Those grades represent the
tire's ability to stop on wet pavement as meas-
ured under controlled conditionsons pecified
governmentt est surfaces of asphalt and con-
crete. Atire marked Cmay have poor traction
performance.
The safe speed on awet, snow covered or icy
road is always lower than on dry road surfaces.
You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Mercedes-Benzr ecommendsaminimum tread
depth of ãin (4 mm) on all four winter tires.
All about wheels and tires301
Wheels and tires
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