tire size MERCEDES-BENZ GL550 2010 X164 User Guide

dimension front vs. rear), tire rotation is not
possible.
If applicable to your vehicle’s tire
configuration, tires can be rotated according
to the tire manufacturer’s recommended
intervals in the tire manufacturer’s warranty
pamphlet located in your vehicle literature
portfolio. If none is available, tires should be
rotated every 3 000 to 6 000 miles (5 000 to
10 000 km), or sooner if necessary, according
to the degree of tire wear. The same rotation
(spinning) direction must be maintained.
Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder wear
on front tires and tread center wear on rear
tires).
Thoroughly clean the mounting face of wheels
and brake disks, i.e. the inner side of the
wheels/tires, during each rotation. Check for
and ensure proper tire inflation pressure.
For information on wheel change, see “Flat
tire” (Y page 336).
Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires:
:Uniform Tire Quality Grading Standards
(Y page 248)
;DOT, Tire Identification Number
(Y page 253)
=Maximum tire load (Y page 246)?Maximum tire inflation pressure
(Y page 242)
AManufacturerBTire ply material (Y page 254)CTire size designation, load and speed
rating (Y page 251)
DLoad identification (Y page 253)ETire name
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
For more information, see “Rims and tires”
(Y page 365).
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Tire size designation, load and speed
rating:Tire width;Aspect ratio in %=Radial tire code?Rim diameterALoad index BSpeed symbol
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
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 designation.
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 width : indicates the nominal tire width
in millimeters.
Aspect ratio
Aspect ratio ; is the dimensional
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 code = 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” (Y page 252).
Rim diameter
Rim diameter ? is the diameter of the bead
seat, not the diameter of the rim edge. The
rim diameter is indicated in inches (in).
Load index
GWarning!
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
tire failure may be the result which may cause
an accident and/or serious injury to you or
others.
Always replace rims and tires with the same
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.
Load index A is a numerical code associated
with the maximum load a tire can support.
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For example, a load rating of 91 corresponds
to a maximum load of 1356 lb (615 kg) the
tire is designed to support. See also
“Maximum tire load” (Y page 246) where the
maximum load associated with the load index
is indicated in kilograms and lbs.
For additional information on the load index,
see “Load identification” ( Y page 253).
Speed symbol GWarning!
Even when permitted by law, never operate a
vehicle at speeds greater than the maximum
speed rating of the tires.
Exceeding the maximum speed for which tires
are rated can lead to sudden tire failure,
causing loss of vehicle control and possibly
resulting in an accident and/or serious
personal injury and possible death, for you
and for others.
Regardless of the tire speed rating, local
speed limits should be obeyed. Use prudent
driving speeds appropriate to prevailing
conditions.
Speed symbol B indicates the approved
maximum speed (tire speed rating) for the
tire.
Summer tires
IndexSpeed ratingQup to 100 mph (160 km/h)Rup to 106 mph (170 km/h)Sup to 112 mph (180 km/h)Tup to 118 mph (190 km/h)Hup to 130 mph (210 km/h)Vup to 149 mph (240 km/h)Wup to 168 mph (270 km/h)Yup to 186 mph (300 km/h)ZR...Yup to 186 mph (300 km/h)IndexSpeed ratingZR...(..Y)above 186 mph (300 km/h)ZRabove 149 mph (240 km/h)
R 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 ZR18).
To determine the maximum speed
capability of the tire, the service
description for the tire must be referred to.
The service description is comprised of
load index A and speed symbol B.
If your tire includes “ZR” in the size
designation and no service description is
given, the tire manufacturer must be
consulted for the maximum speed
capability.
If a service description is given, the speed
capability is limited by the speed symbol in
the service description. Example:
245/40 ZR18 97Y. In this example, “97Y”
is the service description. The letter “Y”
designates the speed rating and the speed
capability of the tire is limited to 186 mph
(300 km/h).
R Any tire with a speed capability above
186 mph (300 km/h) must include a “ZR”
in the size designation AND the service
description must be placed in parenthesis.
Example: 275/40 ZR 18 (99Y). The “(Y)”
speed symbol in parenthesis designates
the maximum speed capability of the tire
as being above 186 mph (300 km/h).
Consult the tire manufacturer for the actual
maximum permissible speed of the tire.
All-season and winter tires
IndexSpeed ratingQ M+S 17up to 100 mph (160 km/h)T M+S17up to 118 mph (190 km/h)17
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The TIN is a unique identifier. The TIN
facilitates efforts by tire manufactures to
notify purchasers in recall situations or other
safety matters concerning tires. It gives
purchasers the means to easily identify such
tires.
The TIN is comprised of “Manufacturer’s
identification mark” ;, “Tire size” =, “Tire
type code” ? and “Date of manufacture”
A.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
DOT (Department of Transportation)
Tire branding symbol : denotes that the tire
meets requirements of the U.S. Department
of Transportation.
Manufacturer’s identification mark
Manufacturer’s identification mark ;
denotes the tire manufacturer.
New tires have a mark with two symbols.
Retreaded tires have a mark with four
symbols. For more information on retreaded
tires, see (Y page 233).
Tire size
Code = indicates the tire size.
Tire type code
Tire type code ? may, at the option of the
manufacturer, be used as a descriptive code
for identifying significant characteristics of
the tire.
Date of manufacture
The date of manufacture A identifies the
week and year of manufacture.
The first two figures identify the week,
starting with “01” to represent the first full
week of the calendar year. The second two
figures represent the year.
For example, “3208” represents the 32nd
week of 2008.
Tire ply material
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
This marking tells you about the type of cord
and number of plies in the sidewall : and
under the tread ;.
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power seats,
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Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit, and production options
weight.
Maximum permissible tire inflation
pressure
This number is the greatest amount of air
pressure that should ever be put in the tire.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilograms
(150 lb).
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (Pounds per square inch)
A standard unit of measure for air pressure.
Recommended tire inflation pressure
The recommended tire inflation pressure for
normal driving conditions is listed on the Tire
and Loading Information placard located on
the driver’s door B-pillar. It provides best
handling, tread life and riding comfort.
Supplemental information pertaining to
special driving situations can be found on the
tire inflation pressure label on the inside of
the fuel filler flap.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
TIN (Tire Identification Number)
Unique identifier which facilitates efforts by
tire manufacturers to notify purchasers in
recall situations or other safety matters
concerning tires and gives purchasers the
means to easily identify such tires. The TIN is
comprised of “Manufacturer’s identification
mark”, “Tire size”, “Tire type code” and “Date
of manufacture”.
Tire ply composition and material used
This indicates the number of plies or the
number of layers of rubber-coated fabric in
the tire tread and sidewall. Tire
manufacturers also must indicate the ply
materials in the tire and sidewall, which
include steel, nylon, polyester, and others.
Tire speed rating
Part of tire designation (speed symbol);
indicates the speed range for which a tire is
approved.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) times the vehicle’s
designated seating capacity.
Traction
The adhesive friction of a tire on a surface on
which it moves. The amount of grip provided.
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After installing winter tires:XCheck the tire inflation pressure and adjust
it if necessary ( Y page 237).XRestart the tire pressure loss warning
system ( Y page 237) or the Advanced Tire
Pressure Monitoring System (Y page 239).
Snow chains
! Vehicles with Adaptive Damping System
(ADS):
When driving with snow chains, do not
select SPORT mode as this may result in
damage to your vehicle.
! Some tire sizes do not leave adequate
clearance for snow chains. To help avoid
serious damage to your vehicle or tires,
make sure the use of snow chains is
permissible as specified in the “Technical
data” section of this Operator’s Manual.
Snow chains should only be driven on snow-
covered roads at speeds not to exceed
30 mph (50 km/h). Remove chains as soon
as possible when driving on roads without
snow.
Observe the following guidelines when using
snow chains:
R Use of snow chains is not permissible with
all wheel/tire combinations ( Y page 365).
R Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
! If snow chains are mounted to the front
wheels, they may scrape against the body
or axle components. The tires or the vehicle
could be damaged as a result.
R Only use snow chains that are approved by
Mercedes-Benz. Any authorized Mercedes-
Benz Center will be glad to advise you on
this subject.
R Use of snow chains may be prohibited
depending on location. Always check local
and state laws before installing snow
chains.
R Do not use snow chains on the spare wheel.
i When driving with snow chains, you may
wish to switch off the ESP ®
(Y page 63)
before setting the vehicle in motion. This
will improve the vehicle’s traction.
Winter driving instructions
GWarning!
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monoxide
(CO) gases may enter vehicle interior
resulting in unconsciousness and death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
GWarning!
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
GWarning!
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle’s ABS will not prevent
this type of control loss.
Do not engage the transfer case in position
LOW when driving on ice or packed snow. At
speeds below 18 mph (30 km/h) vehicle
steering is adversely affected by the Off-road
ABS.
The most important rule for slippery or icy
roads is to drive sensibly and to avoid abrupt
acceleration, braking and steering
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TiresProblemPossible causes/consequences and M SolutionshUSA only:
Combination
low tire pressure
telltale/TPMS
malfunction
telltale for the
Advanced TPMS
illuminates
continuously.The Advanced TPMS detects a loss of pressure in at least one tire.XCarefully bring the vehicle to a halt, avoiding abrupt steering and
braking maneuvers. Observe the traffic situation around you.XRead and observe messages in the multifunction display
( Y page 287).
If the tire inflation pressure in the respective tire(s) has (have) been
corrected, the combination low tire pressure/TPMS malfunction
telltale goes out after a few minutes of driving.
hUSA only:
Combination
low tire pressure
telltale/TPMS
malfunction
telltale for the
Advanced TPMS
flashes 60
seconds and
then stays
illuminated.There is a malfunction in the Advanced TPMS.XRead and observe messages in the multifunction display
( Y page 287).XHave the Advanced TPMS checked at an authorized Mercedes-
Benz Center.
After the malfunction has been remedied, the combination low tire
pressure/TPMS malfunction telltale goes out after a few minutes
of driving.
GWarning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the Tire and Loading
Information placard on the driver’s door B-
pillar or the tire inflation pressure label on the
inside of the fuel filler flap. If your vehicle has
tires of a different size than the size indicated
on the Tire and Loading Information placard
or the tire inflation pressure label, you should
determine the proper tire inflation pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle’s
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire
maintenance, and it is the driver’s
responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately 1 minute and then
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Lifting the vehicleGWarning!
When jacking up the vehicle, only use the jack
which has been specifically approved by
Mercedes-Benz for your vehicle.
The jack is designed exclusively for jacking up
the vehicle at the jack take-up brackets built
into both sides of the vehicle. Make sure the
jack arm is fully seated in the jack take-up
bracket. The jack must always be vertical
when in use, especially on inclines or
declines.
The jack is intended only for lifting the vehicle
briefly for wheel changes. It is not suited for
performing maintenance work under the
vehicle. To help avoid personal injury, use the
jack only to lift the vehicle during a wheel
change.
Never get beneath the vehicle while it is
supported by the jack. Keep hands and feet
away from the area under the lifted vehicle.
Always lower the vehicle onto sufficient
capacity jackstands before working under the
vehicle.
Always engage the parking brake firmly and
block the wheels with wheel chocks or other
sizeable objects before raising the vehicle
with the jack. Do not disengage the parking
brake while the vehicle is raised.
Make sure that the ground on which the
vehicle is standing and where you place the
jack is solid, level and not slippery. If
necessary, use a large underlay. On slippery
surfaces, such as tiled floors, you should use
a non-slip underlay, for example a rubber mat.
Do not use wooden blocks or similar objects
to support the jack. Otherwise the jack may
not be able to achieve its load-bearing
capacity if it is not at its full height.
Never start the engine when the vehicle is
raised.
Also observe the notes on the jack.
XPrevent the vehicle from rolling away by
blocking wheels with wheel chocks or other
sizeable objects.
When your vehicle is equipped with a wheel
chock, it is included with the vehicle tool kit
(Y page 284). For information on setting up
the collapsible wheel chock, see
(Y page 286).
GWarning!
Only jack up the vehicle on level ground or on
slight inclines/declines. Otherwise, the
vehicle could fall off the jack and injure you or
others.
Changing a wheel on a level surface
Changing rear wheel on passenger side (exampleillustration)
XPlace a wheel chock or other sizeable
object in front of and another wheel chock
or other sizeable object behind the wheel
that is diagonally opposite to the wheel
being changed.
Changing a wheel on a slight decline
Always try lifting the vehicle using the jack on
a level surface. However, should
circumstances require you to do so on a slight
decline:
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Changing wheel on passenger side (exampleillustration)
XPlace wheel chocks or other sizeable
objects on the downhill side in front of both
wheels on the side opposite to the side on
which the wheel is to be changed.
Changing a wheel on a slight incline
Always try lifting the vehicle using the jack on
a level surface. However, should
circumstances require you to do so on a slight
incline:
Changing wheel on passenger side (exampleillustration)
XPlace wheel chocks or other sizeable
objects on the downhill side in front of both
wheels on the side opposite to the side on
which the wheel is to be changed.
XOn the wheel to be changed, loosen but do
not yet remove the wheel bolts
(approximately one full turn with wheel
wrench :).
XAssemble the jack (Y page 286).
The jack take-up brackets are located directly
behind the front wheel housings and in front
of the rear wheel housings.
GWarning!
The jack is designed exclusively for jacking up
the vehicle at the jack take-up brackets. Make
sure the jack arm is fully seated in the jack
take-up bracket.
If you do not position the jack correctly in the
jack take-up bracket, the vehicle can fall off
the jack and seriously or fatally injure you or
others.
! Do not position the jack on the body of
the vehicle, as this may cause damage to
the vehicle.
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GWarning!
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
110 lb-ft (150 Nm).
XFully collapse the jack to storage position,
see ( Y page 286).XStore the jack and the other vehicle tools
in the designated storage space.
For information on storing the spare wheel
after it has been replaced by a regular road
wheel, see ( Y page 286).
i The damaged road wheel cannot be
stored in the spare wheel well under the
cargo compartment floor. It should be
transported in the cargo compartment
wrapped in a protective wrap.
i USA only:
Do not restart the tire inflation pressure
monitor until a full size wheel/tire with
functioning sensor has been placed back
into service on the vehicle.
MOExtended system
The MOExtended system allows you to
continue driving your vehicle even if there is
a total loss of pressure in one or more tires.
You may only use the MOExtended system in
conjunction with the tire pressure loss
warning system ( Y page 237) or the
Advanced TPMS ( Y page 239).
The maximum distance in emergency mode
depends on the vehicle’s load. It is 50 miles
(80 km) if the vehicle is partially loaded and
18 miles (30 km) if the vehicle is fully loaded.
The point at which the maximum driving
distance in emergency mode begins is when
the warning message appears in the
multifunction display indicating that there is
a loss of tire inflation pressure.
XDo not exceed the maximum speed of
50 mph (80 km/h).GWarning!
In emergency mode, your vehicle’s driving
characteristics are diminished in such
situations as:
R driving around curves
R while braking
R while accelerating rapidly
Therefore, your driving style must be adapted
accordingly. Avoid abrupt steering and driving
maneuvers, as well as driving over obstacles
(road curbs, potholes, or off-road areas). This
is especially important if the vehicle is heavily
loaded.
The emergency driving distance that can be
achieved greatly depends on the demands
placed on the vehicle. Depending on speed,
load, driving maneuvers, road conditions,
outside temperature, etc., the distance can be
significantly shorter or, if the vehicle is driven
cautiously, somewhat longer.
Do not continue driving in emergency mode if
R you notice knocking sounds
R the vehicle starts to shake
R smoke develops and you smell rubber
R ESP ®
is intervening continuously
R you notice tears on the tire sidewalls
After driving in emergency mode, you must
have the rims inspected by an authorized
Mercedes-Benz Center to check if they are
suitable for further use. The failed tire must
be replaced in any case.
When replacing individual or all tires on the
vehicle, make sure only tires marked with
“MOExtended” are mounted in the size
specified for your vehicle ( Y page 365).
Bleeding the fuel system (diesel
engine only)
Driving the vehicle until the fuel tank is empty
is not recommended. Otherwise, air may be
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