2019 MERCEDES-BENZ GLS SUV wheel size

R
tears in the tires
R bulges on tires
R deformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width of
all tires (Y page 353). If necessary, turn the
front wheels to full lock in order to inspect the
inner side of the tire surface.
All wheels must have a valve cap to protect the
valve against dirt and moisture. Do not mount
anything onto the valve other than the standard valve cap or other valve caps approved by
Mercedes-Benz for your vehicle. Do not use any other valve caps or systems, e.g. tire pressure
monitoring systems.
Regularly check the pressure of all the tires par- ticularly prior to long trips. Adjust the tire pres-
sure as necessary (Y page 355).
Observe the notes on the emergency spare
wheel (Y page 378).
The service life of tires depends, among other
things, on the following factors:
R Driving style
R Tire pressure
R Distance covered Notes on tire tread
G
WARNING
If there is insufficient tire tread, the tire trac-
tion decreases. The tire tread is no longer able to dissipate water. This increases the risk of
hydroplaning when the road surface is wet,
particularly when the vehicle's speed is not
adapted to the road conditions. There is a risk
of an accident.
When the tire pressure is too high or too low,
tires may wear differently at different points
on the tire tread. Therefore, regularly check
the tire tread depth and the condition of the
tread across the whole width of all tires.
Minimum tire tread depth on:
R Summer tires: 00CEin (3 mm)
R M+S tires: 00CFin (4 mm)
For safety reasons, have the tires replaced
before they reach the legally prescribed min-
imum tire tread depth. Marking
0043shows where the bar indicator
(arrow) for tread wear is integrated into the tire
tread.
Treadwear indicators (TWI) are required by law. Six indicators are positioned on the tire tread.
They are visible once a tread depth of approx-
imately 00CDin (1.6 mm) has been reached. If this
is the case, the tire is so worn that it must be
replaced. Selecting, mounting and replacing
tires
R Only mount tires and wheels of the same type
and make.
Exception: it is permissible to mount a differ-
ent type or make in the event of a flat tire.
Observe here the "MOExtended tires (tires
with run-flat characteristics)" section
(Y page 336).
R Only mount tires of the correct size onto the
wheels.
R Break in new tires at moderate speeds for the
first 60 miles (100 km). The new tires only
reach their full performance after this dis-
tance.
R Do not drive with tires which have too little
tread depth. This significantly reduces the
traction on wet roads (hydroplaning).
R Replace the tires after six years at the latest,
regardless of wear.
Observe the notes on the emergency spare
wheel (Y page 378). MOExtended tires (tires with run-flat
properties)
With MOExtended tires (tires with run flat char- acteristics), you can continue to drive your vehi- Operation
353Wheels and tires Z

R
incorrectly set tire pressure
R sudden loss of tire pressure, e.g. from a for-
eign object that has penetrated the tire
The data on the Tire and Loading Information
placard and tire pressure table shown here are
examples. Tire pressure specifications are vehi- cle-specific and may deviate from the data
shown here. The tire pressure specifications
that are valid for your vehicle can be found on
the Tire and Loading Information placard and
tire pressure table on the vehicle.
General notes The recommended tire pressures for the tires
mounted at the factory can be found on the
labels described here.
Operation with emergency spare wheel:
information on operation with the emergency
spare wheel can be found under "Emergency
spare wheel" (Y page 378).
Operation with a trailer: the applicable value
for the rear axle is the maximum tire pressure
value stated in the table inside the fuel filler flap.
Further information on tire pressures can be
obtained at a qualified specialist workshop.
Tire and Loading Information placard Recommended tire pressures
The Tire and Loading Information placard is on
the B-pillar on the driver's side (Y page 362).
The Tire and Loading Information placard con-
tains the recommended tire pressures for cold
tires. The recommended tire pressures are valid for the maximum permissible load and up to the
maximum permissible vehicle speed. Tire pressure table The tire pressure table is on the inside of the fuel
filler flap. It shows the tire pressure for all tires
permitted at the factory for this vehicle; see
illustration (example). The tire pressure table contains the recommen-
ded pressures for cold tires for various operat-
ing conditions, i.e. differing load and speed con-
ditions.
If a tire size precedes a tire pressure, the fol-
lowing tire pressure information is only valid for that tire size; see illustration (example). The load conditions "partially laden" and "fully
laden" are defined in the table for different num- bers of occupants and amounts of luggage. The
actual number of seats may differ. 356
Tire pressureWheels and tires

Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g. R18.
The rim diameter is part of the tire size and can
be found on the tire sidewall (Y page 367).
If the tire pressures have been set to the lower
values for lighter loads and/or lower road
speeds, the pressures should be reset to the
higher values:
R if you want to drive with an increased load
and/or
R if you want to drive at higher speeds
The tire pressures for increased loads and/or
higher road speeds, shown in the tire pressure
table, may have a negative effect on driving
comfort.
If the tire pressure is not set correctly, this can
lead to an excessive build up of heat and a sud- den loss of pressure.
For more information, contact a qualified spe-
cialist workshop. Important notes on tire pressure
G
WARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident. R Check the tire for foreign objects.
R Check whether the wheel is losing air or the
valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop. G
WARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded and malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire pres- sure monitors keep the tire valve open. This
can also result in tire pressure loss. There is a
risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the tire
pressure. The outer appearance of a tire does not permit any reliable conclusion about the tire
pressure. On vehicles equipped with the elec-
tronic tire pressure monitor, the tire pressure
can be checked in the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is dependent
on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold.
The tires are cold:
R if the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
R if the vehicle has not been driven further than
1 mile (1.6 km)
The tire temperature changes depending on the
outside temperature, the vehicle speed and the
tire load. If the tire temperature changes by
18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure of
warm tires. Only correct the tire pressure if it is too low for the current operating conditions. If
you check the tire pressure when the tires are
warm, the resulting value will be higher than if
the tires were cold. This is normal. Do not
reduce the tire pressure to the value specified
for cold tires. The tire pressure would otherwise
be too low.
Observe the recommended tire pressures for
cold tires:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table in the fuel filler flap
(Y page 156)
R printed in yellow on the rim of the emer-
gency/collapsible spare wheel (depending on
vehicle equipment) Underinflated or overinflated tires
Underinflated tires G
WARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition, they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak-ing properties and the driving characteristics.There is a risk of an accident. Tire pressure
357Wheels and tires
Z

Information on tire pressures is displayed in the
multifunction display. After a few minutes of
driving, the current tire pressure of each tire is
shown in the Serv.
Serv. menu of the multifunction
display, see illustration (example). For information on the message display, refer to
the "Checking the tire pressure electronically"
section (Y page 361).
Important safety notes G
WARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended by the vehicle manufacturer on
the Tire and Loading Information placard on
the driver's door B-pillar or the tire 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 Infor-
mation placard or the tire pressure label, you should determine the proper tire 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 pres-
sure 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 underin-
flated tire causes the tire to overheat and can lead to tire failure. Underinflation also
reduces fuel efficiency and tire tread life, andmay affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er'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.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate if 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 warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the vehi-
cle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal low tire pressure as intended. TPMS malfunc-tions may occur for a variety of reasons,
including the mounting of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function telltale after replacing one or more
tires or wheels on your vehicle to ensure that
the replacement or alternate tires and wheels
allow the TPMS to continue to function prop-
erly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 355). Note that the correct tire pressure
for the current operating situation must first be
taught-in to the tire pressure monitor. If a sub-
stantial loss of pressure occurs, the warning
threshold for the warning message is aligned to the taught-in reference values. Restart the tire
pressure monitor after adjusting the pressure of
the cold tires (Y page 362). The current pres-
sures are saved as new reference values. As a
result, a warning message will appear if the tire
pressure drops significantly.
The tire pressure monitor does not warn you of
an incorrectly set tire pressure. Observe the
notes on the recommended tire pressure
(Y page 355).
The tire pressure monitor is not able to warn you of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a 360
Tire pressureWheels and tires

and Loading Information placard shows the
maximum permissible number of occu-
pants and the maximum permissible vehicle
load. It also contains details of the tire sizes and corresponding pressures for tires
mounted at the factory.
(2) The vehicle identification plate is on the B- pillar on the driver's side. The vehicle iden-
tification plate informs you of the gross
vehicle weight rating. It is made up of the
vehicle weight, all vehicle occupants, the
fuel and the cargo. You can also find infor-
mation about the maximum gross axle
weight rating on the front and rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried by one axle (front or rear axle). Never exceed
the maximum load or the maximum gross
axle weight rating for the front or rear axle. 0043
B-pillar, driver's side Maximum permissible gross vehicle
weight rating
X
Specification for maximum gross vehicle
weight 0043is listed in the Tire and Loading
Information placard: "The combined weight of occupants and cargo should never exceed
XXX kilograms or XXX lbs."
The gross weight of all vehicle occupants, load
and luggage must not exceed the specified
value.
i The specifications shown on the Tire and
Loading Information placard in the illustration are examples. The maximum permissible
gross vehicle weight rating is vehicle-specific
and may differ from that in the illustration.
You can find the valid maximum permissible
gross vehicle weight rating for your vehicle on
the Tire and Loading Information placard. Number of seats
Maximum number of seats
0043indicates the
maximum number of occupants allowed to
travel in the vehicle. This information can be
found on the Tire and Loading Information plac-
ard. Loading the vehicle
363Wheels and tires Z

i
The specifications shown on the Tire and
Loading Information placard in the illustration
are examples. The number of seats is vehicle- specific and can differ from the details shown.
The number of seats in your vehicle can be
found on the Tire and Loading Information
placard. Determining the correct load limit
Step-by-step instructions The following steps have been developed as
required of all manufacturers under Title 49,
Code of U.S. Federal Regulations, Part 575 pur- suant to the "National Traffic and Motor Vehicle
Safety Act of 1966".
X Step 1: Locate the statement "The combined
weight of occupants and cargo should never exceed XXX kg or XXX lbs." on your vehicle’s
Tire and Loading Information placard.
X Step 2: Determine the combined weight of
the driver and passengers that will be riding in your vehicle.
X Step 3: Subtract the combined weight of the
driver and passengers from XXX kilograms or
XXX lbs.
X Step 4: The resulting figure equals the avail-
able amount of cargo and luggage load capa-
city. For example, if the "XXX" amount equals 1400 lbs and there will be five 150-lb pas-
sengers in your vehicle, the amount of avail-
able cargo and luggage load capacity is
650 lbs (1400 - 750 (5 x 150) = 650 lbs).
X Step 5: Determine the combined weight of
luggage and cargo being loaded on the vehi-
cle. That weight may not safely exceed the
available cargo and luggage load capacity cal- culated in step 4. Example: steps 1 to 3
The following table shows examples on how to calculate total and cargo load capacities with varying seating configurations and number and size of occupants. The following examples use a load limit of
1500 lbs (680 kg). This is for illustration purposes only. Make sure you are using the actual load
limit for your vehicle stated on your vehicle's Tire and Loading Information placard (Y page 362).
The greater the combined weight of the occupants, the lower the maximum luggage load.
Additional information when towing a trailer (Y page 222).
Step 1 Example 1 Example 2 Example 3
Combined maximum
weight of occupants
and cargo (data from
the Tire and Loading
Information placard)
1500 lbs (680 kg) 1500 lbs (680 kg) 1500 lbs (680 kg)
Step 2
Example 1 Example 2 Example 3
Number of people in
the vehicle (driver and
occupants)
5 3 1
Distribution of the
occupants
Front: 2
Rear: 3 Front: 1
Rear: 2 Front: 1364
Loading the vehicleWheels and tires

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. Sus- tained 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 0043
Uniform Tire Quality Grading Standards
(Y page 370)
0044 Department of Transportation, Tire Identifi-
cation Number (Y page 370)
0087 Maximum load rating (Y page 369)
0085 Maximum tire pressures (Y page 358)
0083 Manufacturer
0084 Tire material (Y page 370)
006B Tire size designation, load-bearing capacity
and speed rating (Y page 367)
006C Load index (Y page 369)
006D 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 deviate
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 bursting. 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. 0043
Tire width
0044 Nominal aspect ratio in %
0087 Tire code
0085 Rim diameter
0083 Load bearing index
0084 Speed rating
General: depending on the manufacturer's
standards, the size imprinted in the tire wall may not contain any letters or may contain one letterthat 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. All about wheels and tires
367Wheels and tires Z

If "LT" precedes the size description: these are
light truck tires according to U.S. manufacturing standards.
If "T" precedes the size description: compact
emergency wheels with high tire pressure that
are only designed for temporary use in an emer-
gency.
Tire width: tire width0043shows the nominal tire
width in millimeters.
Height-width ratio: aspect ratio0044is the size
ratio between the tire height and tire width and is shown in percent. The aspect ratio is calcula-ted by dividing the tire width by the tire height.
Tire code: tire code0087specifies the tire type.
"R" represents radial tires; "D" represents diag-
onal 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 diameter0085is 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 index0083is a
numerical code that specifies the maximum
load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum permissible
load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on
the driver's side (Y page 362).
Example:
Load-bearing index 91 indicates a maximum
load of 1,356 lb (615 kg) that the tires can bear.
For further information on the maximum tire
load in kilograms and lbs, see (Y page 369).
For further information on the load bearing
index, see "Load index" (Y page 369).
Speed rating: speed rating0084specifies the
approved maximum speed of the tire.
i Tire data is vehicle-specific and may deviate
from the data in the example.
Regardless of the speed rating, always observe
the speed limits. Drive carefully and adapt your
driving style to the traffic conditions. Summer tires Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)
S up to 112 mph (180 km/h)
T up to 118 mph (190 km/h)
H up to 130 mph (210 km/h)
V up to 149 mph (240 km/h)
W up to 168 mph (270 km/h)
Y up to 186 mph (300 km/h)
ZR...Y up to 186 mph (300 km/h)
ZR...(..Y) over 186 mph (300 km/h)
ZR over 149 mph (240 km/h)
R
Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR" in
the size description, depending on the man-
ufacturer (e.g. 245/40 ZR18).
The service specification is made up of load-
bearing index 0083and speed rating 0084.
R If the size description of your tire includes
"ZR" and there are no service specifications,
ask the tire manufacturer in order to find out
the maximum speed.
If a service specification is available, the max-
imum speed is limited according to the speed rating in the service specification. Example:
245/40 ZR18 97 Y.In this example, "97 Y" is
the service specification. The letter "Y" rep-
resents the speed rating. The maximum
speed of the tire is limited to 186 mph
(300 km/h).
R The size description for all tires with maxi-
mum speeds of over 186 mph (300 km/h)
must include "ZR", andthe service specifica-
tion must be given in parentheses. Example:
275/40 ZR 18 (99 Y). Speed rating "(Y)" indi- cates that the maximum speed of the tire is
over 186 mph (300 km/h). Ask the tire man-
ufacturer about the maximum speed. 368
All about wheels and tiresWheels and tires