2019 MERCEDES-BENZ GLS SUV light

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

sudden loss of pressure, bring the vehicle to a
halt by braking carefully. Avoid abrupt steering
movements.
The tire pressure monitor has a yellow warning
lamp in the instrument cluster for indicating
pressure loss or a malfunction. Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitor is malfunctioning:
R if the warning lamp is lit continuously, the tire
pressure on one or more tires is significantly
too low. The tire pressure monitor is not mal- functioning.
R if the warning lamp flashes for approximately
a minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
In addition to the warning lamp, a message
appears in the multifunction display. Observe
the information on display messages
(Y page 268).
It may take up to ten minutes for a malfunction
of the tire pressure monitor to be indicated. A
malfunction will be indicated by the tire pres-
sure warning lamp flashing for approximately
one minute and then remaining lit. When the
malfunction has been rectified, the tire pressure warning lamp goes out after a few minutes of
driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured at a gas station with a pressure gauge. The
tire pressures shown by the on-board computer
refer to those measured at sea level. At high
altitudes, the tire pressure values indicated by a pressure gauge are higher than those shown by
the on-board computer. In this case, do not
reduce the tire pressures.
The operation of the tire pressure monitor can
be affected by interference from radio transmit- ting equipment (e.g. radio headphones, two-wayradios) that may be being operated in or near the
vehicle.
Checking the tire pressure electroni-
cally X
Make sure that the SmartKey is in position 0048
(Y page 140) in the ignition lock.
X Press the 0059or0065 button on the steering
wheel to select the Serv.
Serv. menu. X
Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press 0076.
The current tire pressure of each tire is shown in the multifunction display.
If the vehicle has been parked for longer than
20 minutes, the Tire pressure will be Tire pressure will be
displayed after driving a few minutes
displayed after driving a few minutes
message appears.
After a teach-in process, the tire pressure mon-
itor automatically detects new wheels or new
sensors. As long as a clear allocation of the tire
pressure value to the individual wheels is not
possible, the Tire
Tire Pressure Pressure Monitor
MonitorActive
Active
display message is shown instead of the tire
pressure display. The tire pressures are already being monitored.
If an emergency spare wheel is mounted, the
system may continue to show the tire pressure
of the wheel that has been removed for a few
minutes. Therefore, remember that the dis-
played tire pressure may not be the same as the
emergency spare wheel's current tire pressure.
Tire pressure monitor warning mes-
sages If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message is
shown in the multifunction display. The yellow
tire pressure warning lamp then lights up.
R If the Please Correct Tire Pressure Please Correct Tire Pressure
message appears in the multifunction display, the tire pressure in at least one tire is too low.
The tire pressure must be corrected when the
opportunity arises.
R If the Check Tires Check Tires message appears in the
multifunction display, the tire pressure in at
least one tire has dropped significantly. The
tires must be checked.
R If the Warning Warning Tire
TireMalfunction
Malfunction message
appears in the multifunction display, the tire
pressure in at least one tire has dropped sud-
denly. The tires must be checked.
Be sure to observe the instructions and safety
notes in the display messages in the "Tires" sec-
tion (Y page 268).
If the positions of the wheels on the vehicle are changed, the tire pressures may be displayed in
the wrong positions for a short time. This is rec-
tified after a few minutes of driving, and the tire pressures are displayed for the correct posi-
tions. Tire pressure
361Wheels 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

All-weather tires and winter tires
Index Speed rating
Q M+S
3 up to 100 mph (160 km/h)
T M+S
3 up to 118 mph (190 km/h)
H M+S
3 up to 130 mph (210 km/h)
V M+S
3 up to 149 mph (240 km/h)
i
Not all tires with the M+S marking provide
the driving characteristics of winter tires. In
addition to the M+S marking, winter tires also
have the 004Dsnowflake symbol on the tire
wall. Tires with this marking fulfill the require- ments of the Rubber Manufacturers Associa-
tion (RMA) and the Rubber Association of
Canada (RAC) regarding the tire traction on
snow. They have been especially developed
for driving on snow.
An electronic speed limiter prevents your vehi-
cle from exceeding the following speeds:
R All vehicles (except Mercedes-AMG GLS 63):
130 mph (210 km/h)
R Mercedes-AMG GLS 63: 155 mph (250 km/h)
R Mercedes-AMG GLS 63 with increased top
speed: 174 mph (280 km/h)
The speed rating of tires mounted at the factory may be higher than the maximum speed that the
electronic speed limiter permits.
Make sure that your tires have the required
speed rating, e.g. when buying new tires. The
required speed rating for your vehicle can be
found in the "Tires" section (Y page 377).
Further information about reading tire data can
be obtained from any qualified specialist work-
shop. Load index In addition to the load bearing index, load
index
0043may be imprinted after the letters that
identify speed index 0084on the sidewall of the
tire (Y page 367).
R If no specification is given: no text (as in the
example above), represents a standard load
(SL) tire
R XL or Extra Load: represents a reinforced tire
R Light Load: represents a light load tire
R C, D, E: represents a load range that depends
on the maximum load that the tire can carry at a certain pressure
i Tire data is vehicle-specific and may deviate
from the data in the example.
Maximum load rating Maximum tire load
0043is the maximum permis-
sible weight for which the tire is approved.
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).
3 Or M+S 004Dfor winter tires. All about wheels and tires
369Wheels and tires Z

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 out-
ward force to each square inch of the tire's sur-
face. 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.
Cold tire pressure
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)
Tread
The part of the tire that comes into contact with
the road.
BeadThe 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
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-per-
formance battery, are not included in the curb
weight and the weight of the accessories.
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 pur-
chasers. The TIN is made up of the manufactur-
er'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 capa-
city 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.
Treadwear indicators Narrow bars (tread wear bars) that are distrib-
uted over the tire tread. If the tire tread is level
with the bars, the wear limit of 00CDin (1.6 mm)
has been reached.
Occupant distribution
The distribution of occupants in a vehicle at their designated seating positions.
Total load limit Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle. Changing a wheel
Flat tire
The "Breakdown assistance" section
(Y page 335) contains information and notes on
how to deal with a flat tire. Information on driv-
ing with MOExtended tires in the event of a flat
tire can be found under "MOExtended tires (tires with run-flat characteristics" (Y page 336).
Vehicles with an emergency spare wheel: in
the event of a flat tire, mount the emergency
spare wheel according to the description under "Mounting a wheel" (Y page 373). Rotating the wheels
G
WARNING
Rotating the front and rear wheels if the
wheels or tires have different dimensions may severely impair the driving characteristics.
The service brake or wheel suspension com- 372
Changing a wheelWheels and tires

compartment with the carrying strap at the
back.
X Hook retaining spring hooks 0043of fastening
strap 0044into the cargo tie-down rings.
X Tighten fastening strap 0044.Inflating the collapsible spare wheel
(Mercedes-AMG GLS 63 4MATIC)
! Inflate the collapsible spare wheel using the
tire inflation compressor before lowering the
vehicle. The wheel rim could otherwise be
damaged.
! Do not operate the tire inflation compressor
for longer than eight minutes at a time without
a break. It may otherwise overheat.
The tire inflation compressor can be operated again once it has cooled down.
Comply with the manufacturer's safety instruc-
tions on the tire inflation compressor label and
on the tire sealant bottle.
X Mount the collapsible spare wheel as descri-
bed (Y page 373).
The collapsible spare wheel must be mounted before it is inflated.
X Remove the tire inflation compressor from
the stowage space under the cargo compart-
ment floor (Y page 335). X
Pull connector 0085and hose 0084out of the
housing.
X Remove the cap from the valve on the col-
lapsible spare wheel.
X Screw union nut 0044of hose 0084onto the valve.
X Make sure on/off switch 0083of the tire infla-
tion compressor is set to 0.
X Insert connector 0085into a socket in your vehi-
cle. Cigarette lighter socket: (Y
page 307)
12 V sockets: (Y page 307)
Observe the notes on the cigarette lighter
(Y page 307). Observe the notes on sockets
(Y page 307).
X Turn the SmartKey to position 0047in the igni-
tion lock (Y page 140).
X Press on and off switch 0083on the tire inflation
compressor to I.
The tire inflation compressor is switched on.
The tire is inflated. The tire pressure is shown on pressure gauge 0087.
X Inflate the tire to the specified tire pressure.
The specified tire pressure is printed on the
yellow label of the emergency spare wheel.
X When the specified tire pressure has been
reached, press on and off switch 0083on the
tire inflation compressor to 0.
The tire inflation compressor is switched off.
X Turn the SmartKey to position 0092in the igni-
tion lock.
X If the tire pressure is higher than the specified
pressure, press pressure release valve but-
ton 0043until the correct tire pressure has been
reached.
X Unscrew union nut 0044on hose 0084from the
valve.
X Screw the cap onto the valve of the collapsi-
ble spare wheel again.
X Stow connector 0085and hose 0084in the lower
section of the tire inflation compressor.
X Stow the tire inflation compressor in the vehi-
cle. Emergency spare wheel
381Wheels and tires Z