Diff MERCEDES-BENZ GL-Class 2015 X166 Repair Manual

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops (Y page 29). Where will I find...?
Vehicle tool kit
General notes The vehicle tool kit can be found in the stow-
age well under the cargo compartment floor.
i Apart from certain country-specific varia-
tions, the vehicles are not equipped with a
tire-change tool kit. Some tools for chang-
ing a wheel are specific to the vehicle. For
more information on which tools are
required to perform a wheel change on your vehicle, consult a qualified specialist work-
shop.
Tools required for changing a wheel may
include, for example:
R Jack
R Wheel chock
R Lug wrench
R Ratchet wrench
R Alignment bolt Vehicles with a TIREFIT kit 0043
Lug wrench
0044 Towing eye
0087 Ratchet wrench
0085 Alignment bolt
0083 Tire sealant filler bottle
0084 Tire inflation compressor
006B Folding wheel chock
006C Jack
006D Wheel bolts
X Lift the cargo compartment floor up
(Y page 349).
X Use the TIREFIT kit (Y page 390).
Vehicles with a "Minispare" emergency spare wheel 0043
Alignment bolt
0044 Velcro fastener
0087 Folding wheel chock
0085 Ratchet wrench
0083 Lug wrench
0084 Jack 388
Where will I find...?Breakdown assistance

!
Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could
be damaged.
! Do not use the trailer tow hitch for recov-
ery or towing. Do not use the towing eye for
recovery. this could damage the vehicle. If
in doubt, have the vehicle recovered using
a crane.
! When towing, pull away slowly and
smoothly. Pull the towed vehicle as straight
as possible and not at an acute angle.
Excessive tractive power could damage the
vehicles.
i When towing, it is preferable to use a rigid
towing bar as opposed to a tow rope. A rigid
towing bar helps to keep the tractive power low.
! When towing vehicles with KEYLESS-GO,
use the key instead of the Start/Stop but-
ton. Otherwise, the automatic transmission
may shift to position Pwhen the driver's or
front-passenger door are opened, which
could lead to damage to the transmission.
! Do not tow with sling-type equipment.
This could damage the vehicle.
! Vehicles with differential locks: make
sure the differential locks are in automatic
mode. When towing, the differential locks
must not be switched on. The transmission
may otherwise be damaged.
! The vehicle can be towed a maximum of
30 miles (50km). The towing speed of
30 mph (50 km/h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the entire vehicle must be
raised and transported.
! If you tow or tow-start another vehicle, its
weight must not exceed the maximum per- missible gross vehicle weight of your vehi-
cle.
i Information on your vehicle's gross vehi-
cle weight rating can be found on the vehi-
cle identification plate (Y page 446).It is better to have the vehicle transported
than to have it towed.
If the vehicle has suffered transmission dam-
age, have it transported on a transporter or
trailer.
The automatic transmission must be in posi-
tion Nwhen the vehicle is being towed.
The battery must be connected and charged.
Otherwise, you:
R cannot turn the SmartKey to position 2in
the ignition lock
R cannot release the electric parking brake
R cannot shift the automatic transmission to
position N
i Disarm the automatic locking feature
before the vehicle is towed (Y page 287).
You could otherwise be locked out when
pushing or towing the vehicle. Installing/removing the towing eye
Installing the towing eye Example: towing eye mounting covers
0043 Front cover
0044 Back cover
The brackets for the screw-in towing eyes are
located in the bumpers. They are at the front and at the rear, behind the covers. 400
Towing and tow-startingBreakdown assistance

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops (Y page 29). Important safety notes
G
WARNING
If wheels and tires of the wrong size are used, the wheel brakes or suspension components
may be damaged. There is a risk of an acci-
dent.
Always replace wheels and tires with those
that fulfill the specifications of the original
part.
When replacing wheels, make sure to use the
correct:
R designation
R model
When replacing tires, make sure to use the
correct:
R designation
R manufacturer
R model G
WARNING
A flat tire severely impairs the driving, steer-
ing and braking characteristics of the vehicle.
There is a risk of accident.
Tires without run-flat characteristics:
R do not drive with a flat tire.
R immediately replace the flat tire with your
emergency spare wheel or spare wheel, or
consult a qualified specialist workshop. Tires with run-flat characteristics:
R pay attention to the information and warn-
ing notices on MOExtended tires (tires with
run-flat characteristics).
Accessories that are not approved for your
vehicle by Mercedes-Benz or that are not
being used correctly can impair operating
safety.
Before purchasing and using non-approved
accessories, visit a qualified specialist work-
shop and inquire about:
R suitability
R legal stipulations
R factory recommendations
Information on the dimensions and types of
wheels and tires for your vehicle can be found in the "Wheel/tire combinations" section
(Y page 434).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading Informa-
tion placard on the B-pillar (Y page 418)
R on the tire pressure label on the fuel filler
flap (Y page 187)
R in the "Tire pressure" section Operation
Information on driving
If the vehicle is heavily loaded, check the tire pressures and correct them if necessary.
While driving, pay attention to vibrations,
noises and unusual handling characteristics,
e.g. pulling to one side. This may indicate that
the wheels or tires are damaged. If you sus-
pect that a tire is defective, reduce your
speed immediately. Stop the vehicle as soon
as possible to check the wheels and tires for
damage. Hidden tire damage could also be
causing the unusual handling characteristics. If you find no signs of damage, have the tires
and wheels checked at a qualified specialist
workshop. 406
OperationWheels and tires

When parking your vehicle, make sure that
the tires do not get deformed by the curb or
other obstacles. If it is necessary to drive over
curbs, speed humps or similar elevations, try to do so slowly and at an obtuse angle. Oth-
erwise, the tires, particularly the sidewalls,
may be damaged. Regular checking of wheels and tires
G
WARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control of your vehicle. There is a risk of accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
Regularly check the wheels and tires of your
vehicle for damage at least once a month, as well as after driving off-road or on rough
roads. Damaged wheels can cause a loss of
tire pressure. Pay particular attention to dam-
age such as:
R cuts in the tires
R punctures
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 the tire (Y page 407). 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
particularly prior to long trips. Adjust the tire pressure as necessary (Y page 410).
Observe the notes on the emergency spare
wheel (Y page 440). The service life of tires depends on the fol-
lowing factors amongst other things:
R Driving style
R Tire pressure
R Distance covered Important safety notes on the tire
tread
G
WARNING
Insufficient tire tread will reduce tire traction.
The tire is no longer able to dissipate water.
This means that on wet road surfaces, the risk of hydroplaning increases, in particular where speed is not adapted to suit the driving con-
ditions. There is a risk of accident.
If the tire pressure is too high or too low, tires
may exhibit different levels of wear at differ-
ent locations on the tire tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
width of all tires.
Minimum tire tread depth for:
R Summer tires: 00CEin (3 mm)
R M+S tires: 00CFin (4 mm)
For safety reasons, replace the tires before
the legally prescribed limit for the minimum
tire tread depth is reached. Bar indicator
0043for 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 the tread depth is Operation
407Wheels and tires Z

Tire pressure
Tire pressure specifications
Important safety notes G
WARNING
Underinflated or overinflated tires pose the
following risks:
R the tires may burst, especially as the load
and vehicle speed increase.
R the tires may wear excessively and/or
unevenly, which may greatly impair tire
traction.
R the driving characteristics, as well as steer-
ing and braking, may be greatly impaired.
There is a risk of an accident.
Follow recommended tire inflation pressures
and check the pressure of all the tires includ-
ing the spare wheel:
R monthly, at least
R if the load changes
R before beginning a long journey
R under different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
i The specifications on the sample Tire and
Loading Information placard and tire pres-
sure tables are examples. Tire pressure
specifications are vehicle-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 pres-
sure 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 the emergency spare
wheel(Y page 440).
Operation with a trailer: the applicable
value for the rear tires 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 0043
Recommended tire pressures
The Tire and Loading Information placard is
on the B-pillar on the driver's side
(Y page 418).
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. Example: tire pressure table for all tires permitted
for this vehicle by the factory
The tire pressure table contains the recom-
mended pressures for cold tires for various 410
Tire pressureWheels and tires

operating conditions, i.e. differing load and
speed conditions. Example: tire pressure table with tire dimensions
If a tire size precedes a tire pressure, the tirepressure information following is only valid
for that tire size. The load conditions "partially
laden" and "fully laden" are defined in the
table for different numbers of occupants and
amounts of luggage. The actual number of
seats may differ. 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 423).
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 road speeds
i 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 sudden 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 electronic tire pressure monitoring sys-
tem, the tire pressure can be checked using
the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is depend-
ent on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold. Tire pressure
411Wheels and tires Z

Example: current tire pressure display
For information on the message display, refer to the "Checking the tire pressure electroni-
cally" section (Y page 416).
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 410). Note that the correct tire pres-
sure for the current operating situation must
first be taught-in to the tire pressure monitor. If there is a substantial loss of pressure, the
warning threshold for the warning message isaligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing the pressure of the cold tires
(Y page 417). The current pressures are
saved as new reference values. As a result, a
warning message will appear if the tire pres-
sure 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 410).
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the Tire pressure
415Wheels and tires Z

tire is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
abrupt steering maneuvers.
The tire pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat- ing a pressure loss or malfunction. Whether
the warning lamp flashes or lights up indi-
cates 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 signif- icantly too low. The tire pressure monitor is
not malfunctioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
i In addition to the warning lamp, a mes-
sage appears in the multifunction display.
Further information can be found on
(Y page 320).
If the tire pressure monitor is malfunctioning,
it may take more than ten minutes for the tire pressure warning lamp to inform you of the
malfunction by flashing for approximately one
minute and then remaining lit. When the mal- function 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 val-
ues 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 trans-
mitting equipment (e.g. radio headphones,
two-way radios) 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
2 (Y page 167) in the ignition lock.
X Press the 0059or0065 button on the steer-
ing wheel to select the Service
Service menu.
X Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press the 0076button.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle has been parked for longer than 20 minute s,the Tire pressure will be
Tire pressure will be
displayed after driving a few
displayed after driving a few
minutes minutes message appears.
After a teach-in process, the tire pressure
monitor 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 Pressure Tire Pressure
Monitor Active Monitor Active display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
i 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. If this occurs,
note that the value displayed for the posi-
tion where the spare wheel is mounted is
not the same as the current tire pressure of
the emergency spare wheel.
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 and the yellow tire pressure monitor warning lamp
comes on.
R If the Please Correct Tire Pressure Please Correct Tire Pressure
message appears in the multifunction dis-
play, the tire pressure in at least one tire is 416
Tire pressureWheels and tires

too low and must be corrected at the next
opportunity.
R If the Check
Check Tires
Tiresmessage appears in the
multifunction display, the tire pressure in
one or more tires has dropped significantly
and the tires must be checked.
R If the Warning Tire Malfunction Warning Tire Malfunction
appears in the multifunction display, the
tire pressure in one or more tires has drop- ped suddenly and the tires must be
checked.
i If the wheel positions on the vehicle are
rotated, the tire pressures may be dis-
played for the wrong positions for a short
time. This is rectified after a few minutes of driving, and the tire pressures are displayedfor the correct positions.
Restarting the tire pressure monitor When you restart the tire pressure monitor, all
existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the refer-
ence values for monitoring. In most cases, the
tire pressure monitor will automatically
detect the new reference values after you
have changed the tire pressure. However, you
can also define reference values manually as described here. The tire pressure monitor
then monitors the new tire pressure values.
X Set the tire pressure to the value recom-
mended for the corresponding driving sit-
uation on the Tire and Loading Information
placard on the driver's side
B-pillar (Y page 410).
Additional tire pressure values for different loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(Y page 410).
X Make sure that the tire pressure is correct
on all four wheels.
X Make sure that the SmartKey is in position
2 in the ignition lock.
X Press the 0059or0065 button on the steer-
ing wheel to select the Service
Service menu. X
Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press the 0076button.
The multifunction display shows the cur-
rent tire pressure for the individual tires or
the Tire Tire pressure
pressure will
willbe
bedisplayed
displayed
after driving a few minutes
after driving a few minutes mes-
sage.
X Press the 0064button.
The Use Current Pressures as New
Use Current Pressures as New
Reference Values
Reference Values message appears in
the multifunction display.
If you wish to confirm the restart: X Press the 0076button.
The Tire Press. Monitor Restarted
Tire Press. Monitor Restarted
message appears in the multifunction dis-
play.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored.
If you wish to cancel the restart:
X Press the 0038button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor Country Radio type approval number
USA FCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
Canada IC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4 Tire pressure
417Wheels and tires Z

Loading the vehicle
Instruction labels for tires and loads
G
WARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
Two instruction labels on your vehicle show
the maximum possible load.
(1) The Tire and Loading Information placard is on the B-pillar on the driver's side. The
Tire and Loading Information placard
shows the maximum permissible number
of occupants and the maximum permis-
sible vehicle load. It also contains details
of the tire sizes and corresponding pres-
sures for tires mounted at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight rating. It is made up
of the vehicle weight, all vehicle occu-
pants, the fuel and the cargo. You can
also find information 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 maxi-
mum 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 speci-
fied value.
i The specifications shown on the Tire and
Loading Information placard in the illustra-
tion are examples. The maximum permis-
sible gross vehicle weight rating is vehicle- specific and may differ from that in the
illustration. You can find the valid maximum 418
Loading the vehicleWheels and tires