2012 MERCEDES-BENZ GL-Class width

Maximum tire load : is the maximum
permitted weight for which the tire is
approved.
Further information on tire loads
( Y page 355).
Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards
The Uniform Tire Quality Grading is a U.S.
Government requirement. Their purpose is to
provide drivers with consistent and reliable
information regarding tire performance. Tire
manufacturers are required to grade tires
using three performance factors: tread
wear :, tire traction ;, and temperature
resistance =. Although not a Government of
Canada requirement, all tires made for sale in
North America have these grades branded on
the sidewall.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
For example:
Tread wearTractionTemperature200AAAAll passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climate conditions.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.
GWARNING
If ice has formed on the road, tire traction will
be substantially reduced. Under such weather
conditions, drive, steer and brake with
extreme caution.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road
surfaces.
354Uniform Tire Quality Grading StandardsWheels and tires

Tire size designation, load-bearing
capacity and speed index:Tire width;Nominal aspect ratio in %=Tire code?Rim diameterALoad bearing indexBTire speed rating
i Tire data is vehicle-specific and may
deviate from the data in the example.
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
description (as shown above): these are
passenger vehicle tires according to
European manufacturing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S.
manufacturing standards.
If "T" precedes the size description: these are
compact emergency spare wheels at high tire
pressure, to be used only temporarily in an
emergency.
Tire width: tire width : shows the nominal
tire width in millimeters.
Nominal aspect ratio: aspect ratio ; is the
size ratio between the tire height and the tire
width and is shown in percent. The aspect
ratio is calculated by dividing the tire width by
the tire height.
Tire code: tire code = specifies the tire type.
"R" represents radial tires. "D" represents
diagonal tires, "B" represents diagonal radial
tires.
Optionally, tires with a maximum speed of
over 149 mph(240 km/h) may have "ZR" in
the size description depending on the
manufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter ? is the
diameter of the bead seat, not the diameter
of the rim flange. The rim diameter is
specified in inches (in).
Load bearing index: load bearing index A
is a numerical code which specifies the
maximum load-bearing capacity of a tire.GWARNING
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
sudden tire failure may be the result which
could cause an accident and/or serious injury
to you or others.
Always replace rims and tires with rims and
tires having the same specifications
(designation, manufacturer and type) as
shown on the original part.
GWARNING
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Example:
The load bearing index 91 is equivalent to a
maximum load of 1356 lbs (615 kg) that the
tire can carry. For further information on the
maximum tire load in kilograms and pounds,
see ( Y page 353).
356Tire labelingWheels and tires

Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold. For this,
the vehicle must have been stationary for at
least three hours or not have traveled more
than 1.6 km (1 mile) in this time.
Tire pressure of cold tires
Tire pressure when the vehicle has been
stationary for at least three hours or not have
traveled more than 1.6 km (1 mile) in this
time.
Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
part and more than 2.3 kilograms (5 lbs).
These optional extras, such as high-
performance brakes, level control, a roof rack
or a high-performance battery, are not
included in the curb weight and accessory
weight.
TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identify
the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support.
Definition of terms for tires and loading361Wheels and tiresZ

Windshield/headlamp cleaning
systemGWARNING
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
Use MB SummerFit windshield washer
concentrate at temperatures above freezing:
XMix 1 part MB SummerFit with 100 parts
water.
Use MB WinterFit windshield washer
concentrate at temperatures below freezing:
XAt temperatures down to 14 ‡(Ò 10 †): mix
1 part MB WinterFit with 2 parts water.XAt temperatures down to Ò 4 ‡( Ò 20 †): mix
1 part MB WinterFit with 1 part water.XAt temperatures down to
Ò 20.2 ‡(Ò 29 †): mix 2 parts MB WinterFit
with 1 part water.
! Only SummerFit and WinterFit can be
mixed. Otherwise, the jets could become
blocked.
Vehicle data
Vehicle data, GL 350 BlueTEC
The data stated here refers specifically to a
vehicle with standard equipment. Consult an
authorized Mercedes-Benz Center for the
data for all vehicle variants and trim levels.
Vehicle dimensions, GL 350 BlueTECVehicle length201.1 in (5108 mm)Vehicle width
including exterior
mirrors85.4 in (2170 mm)Vehicle height72.4 - 75.6 in (1840 -
1920 mm) 4972.4 - 76.8 in (1840 -
1950 mm) 50Wheelbase121.1 in (3075 mm)Front track64.8 in (1645 mm)Rear track65.0 in (1650 mm)Ground clearance8.0 - 10.9 in (202 -
277 mm) 498.0 - 12.1 in (202 -
307 mm) 50Turning circle39.7 ft (12.1 m)Vehicle weight, GL 350 BlueTECMaximum roof
loadMaximum 198 lb
(90 kg)
Vehicle data, GL 450
The data stated here refers specifically to a
vehicle with standard equipment. Consult an
authorized Mercedes-Benz Center for the
data for all vehicle variants and trim levels.
49 Vehicles without Off-road Pro engineering package: the values vary depending on the level set for the vehicle
suspension.
50 Vehicles with Off-road Pro engineering package: the values vary depending on the level set for the vehicle
suspension.Vehicle data377Technical dataZ

Vehicle dimensions, GL 450Vehicle length201.1 in (5108 mm)Vehicle width
including exterior
mirrors85.4 in (2170 mm)Vehicle height72.4 - 75.6 in (1840 -
1920 mm) 5172.4 - 76.8 in (1840 -
1950 mm) 52Wheelbase121.1 in (3075 mm)Front track64.8 in (1645 mm)Rear track65.0 in (1650 mm)Ground clearance8.0 - 10.9 in (202 -
277 mm) 518.0 - 12.1 in (202 -
307 mm) 52Turning circle39.7 ft (12.1 m)Vehicle weight, GL 450Maximum roof
loadMaximum 198 lb
(90 kg)
Vehicle data, GL 550
The data stated here refers specifically to a
vehicle with standard equipment. Consult an
authorized Mercedes-Benz Center for the
data for all vehicle variants and trim levels.
Vehicle dimensions, GL 550Vehicle length201.1 in (5108 mm)Vehicle width
including exterior
mirrors85.4 in (2170 mm)Vehicle height72.4 - 75.6 in (1840 -
1920 mm) 5372.4 - 76.8 in (1840 -
1950 mm) 54Wheelbase121.1 in (3075 mm)Front track66.3 in (1683 mm)Rear track66.5 in (1688 mm)Ground clearance8.0 - 10.9 in (202 -
277 mm) 538.0 - 12.1 in (202 -
307 mm) 54Turning circle39.7 ft (12.1 m)Vehicle weight, GL 550Maximum roof
loadMaximum 198 lb
(90 kg)51 Vehicles without Off-road Pro engineering package: the values vary depending on the level set for the vehicle
suspension.
52 Vehicles with Off-road Pro engineering package: the values vary depending on the level set for the vehicle
suspension.
53 Vehicles without Off-road Pro engineering package: the values vary depending on the level set for the vehicle
suspension.
54 Vehicles with Off-road Pro engineering package: the values vary depending on the level set for the vehicle
suspension.378Vehicle dataTechnical data