2018 MERCEDES-BENZ GLS SUV tow bar

ELevel control
FCompass with angle scale
Activating the driving dynamics display
XSwitch on COMAND (see the Digital Opera-
tor's Manual).
XPress button:.
The driving dynamics display appears in the
COMAND display.
Towing a trailer
Important safety notes
GWARNING
Installing an unsuitable ball coupling may
result in overloading of the trailer tow hitch
and the rear axle. This applies especially if the ball coupling in question is longer or angled
differently. This could seriously impair the
driving characteristics and the trailer can
come loose. There is a risk of an accident.
You should only ever install a ball coupling
that has the permissible dimensions and that
is designed to meet your trailer-towing
requirements. Do not modify the ball coupling
or the trailer tow hitch.
You will find the values approved by the manu-
facturer on the vehicle identification plates and
those for the towing vehicle under "Technical
data" (
Ypage 395).
GWARNING
If the ball coupling is not installed correctly or not secured with the bolt provided and the
corresponding spring cotter, the trailer may
come loose. There is a risk of an accident.
Always install and secure the ball coupling asdescribed. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter.
GWARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi- cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary.
Please observe the manufacturer's operating
instructions for the trailer coupling if a detach-
able trailer coupling is used.
Couple and uncouple the trailer carefully. If you
do not couple the trailer to the towing vehicle
correctly, the trailer could become detached.
Make sure that the following values are not
exceeded:
Rthe permissible trailer drawbar noseweight
Rthe permissible trailer load
Rthe permissible rear axle load of the towing
vehicle
Rthe maximum permissible gross vehicle
weight of both the towing vehicle and the
trailer
The applicable permissible values, which must
not be exceeded, can be found:
Rin the vehicle documents
Ron the identification plates for the trailer tow
hitch and the trailer
Ron the vehicle identification plate
If the values differ, the lowest value applies.
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
The vehicle/trailer combination:
Ris heavier
Ris restricted in its acceleration and gradient-
climbing capability
Rhas an increased braking distance
224Towing a trailer
Driving and parking

Ris affected more by strong crosswinds
Rdemands more sensitive steering
Rhas a larger turning circle
This could impair the handling characteristics.
When towing a trailer, always adjust your speed
to the current road and weather conditions. Do
not exceed the maximum permissible speed for
your vehicle/trailer combination.
Notes on towing a trailer
General notes
!If you have a trailer tow hitch retrofitted,
changes to the cooling system and drive train
may be necessary, depending on the vehicle
type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
RDo not exceed the legally prescribed maxi-
mum speed for vehicle/trailer combinations
in the relevant country.
This lowers the risk of an accident.
ROnly install an approved trailer coupling on
your vehicle.
More information on availability and installa-
tion can be obtained at any qualified special-
ist workshop.
RThe bumpers of your vehicle are not suitable
for installing detachable trailer couplings.
RDo not install hired trailer couplings or other
detachable trailer couplings on the bumpers
of your vehicle.
RIf you no longer need the ball coupling,
remove it from the ball coupling recess. This
will reduce the risk of damage to the ball cou-
pling.
When towing a trailer, set the tire pressure on
the rear axle of the towing vehicle for the max-
imum load. You will find the values in the tire
pressure table in the fuel filler flap of the vehicle (
Ypage 372).
Please note that when towing a trailer, the fol-
lowing driving systems have limited availability
or are not available at all:
RParking Assist PARKTRONIC (Ypage 192)
RBlind Spot Assist (Ypage 209)
RActive Lane Keeping Assist (Ypage 215) On vehicles without level control, the height of
the ball coupling will alter according to the load
placed on the vehicle. If necessary, use a trailer
with a height-adjustable drawbar.
You will find installing dimensions and loads
under "Technical data" (
Ypage 395).
Driving tips
Also observe the notes on pulling away with a
trailer (Ypage 143).
The maximum permissible speed for vehicle/
trailer combinations depends on the type of
trailer. Before beginning the journey, check the
trailer's documents to see what the maximum
permissible speed is for your trailer. Observe the
legally permissible maximum speed in the rele-
vant country.
For certain Mercedes-Benz vehicles, the maxi-
mum permissible rear axle load is increased
when towing a trailer. See "Technical data" to
find out whether this applies to your vehicle
(
Ypage 395). If you utilize any of the added
maximum rear axle load when towing a trailer,
the vehicle/trailer combination may not exceed
a maximum speed of 60 mph (100 km/h) for
reasons concerning the operating permit. This
also applies in countries in which the maximum
permissible speed for car/trailer combinations
is greater than 60 mph (100 km/h).
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
Use the left-hand steering wheel paddle shifter
to shift into a lower gear in good time on long
and steep downhill gradients.
This also applies if you have activated cruise
control or Distance Pilot DISTRONIC.
This will use the braking effect of the engine, so that less braking will be required to maintain the
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly. If you need additional
braking, depress the brake pedal repeatedly
rather than continuously.
Driving tips
If the trailer swings from side to side:
XDo not accelerate.
XDo not counter-steer.
XBrake if necessary.
Towing a trailer225
Driving and parking
Z

Most U.S. states and all Canadian provinces
require by law:
RSafety chains between the towing vehicle and
the trailer. The chains should be cross-wound
under the trailer drawbar. They must be fas-
tened to the vehicle's trailer coupling, not to
the bumper or the axle.
Leave enough play in the chains to make tight
cornering possible.
RA separate brake system for certain types of
trailer.
RSafety switch for braked trailers. Check the
specific legal requirements applicable to your
state.
If the trailer becomes detached from the tow-
ing vehicle, the safety feature triggers the
trailer brakes.
Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed restric-
tions. Make sure that your car/trailer combina-tion complies with the local regulations:
Rin your place of residence
Rin the location to which you are driving
The police and local authorities can provide reli-
able information.
Observe the following when towing a trailer:
RTo gain driving experience and to become
accustomed to the new handling characteris-
tics, you should practice the following in a
traffic-free location:
-cornering
-stopping
-backing up
RBefore driving, check:
-trailer tow hitch
-safety switch for braked trailers
-safety chains
-electrical connections
-lights
-wheels
RAdjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
RIf the trailer has electronically controlled
brakes, pull away carefully. Brake manually using the brake controller and check whether
the brakes function correctly.
RSecure any objects on the trailer to prevent
the cargo from slipping when the vehicle is in
motion.
RWhen you couple up a trailer, check at regular
intervals that the load is firmly secured. If the
trailer is equipped with trailer lights and
brakes, check the trailer to ensure that these
are working.
RBear in mind that the handling will be less
stable when towing a trailer than when driving
without one. Avoid sudden steering move-
ments.
RThe vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
RIf possible, do not brake suddenly, but instead
depress the brake pedal moderately at first so
that the trailer can activate its brakes. Then
increase the pressure on the brake pedal.
RIf the automatic transmission repeatedly
shifts between gears on uphill or downhill gra-
dients, shift to a lower gear using the left-hand
steering wheel paddle shifter.
A lower gear and lower speed reduce the risk
of engine failure.
RWhen driving downhill, shift to a lower gear to
utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if instal-
led, the trailer brakes.
RIf the coolant temperature increases dramat-
ically while the air-condit ioning system is
switched on, switch off the air-conditioning
system.
Coolant heat can also be dissipated by open-
ing the windows and switching the ventilation blower and the interior temperature to the
highest level.
RWhen overtaking, pay particular attention to
the extended length of your vehicle/trailer
combination.
Due to the length of the vehicle/trailer com-
bination, you require additional road space in
relation to the vehicle you are overtaking
before you can change back to the original
lane.
228Towing a trailer
Driving and parking

Decouplingatrailer
GWARNING
If you uncoupl e atrailer wit hth eoverrun
brake engaged, you could trap your han d
between th evehicle and th etrailer drawbar .
There is aris kof injury.
Do no tuncoupl e atrailer if th eoverrun brake
is engaged.
GWARNING
Vehicles wit hlevel control:
The vehicle is lowered as soo nas you discon-
nect th etrailer cable. Thi scould result in your
limbs or those of other people that are
between th evehicle bod yand tires or under-
neat hth evehicle bein gtrapped. There is a
ris kof injury.
Mak esur ethat nobod yis in th eimmediate
vicinit yof th ewhee lhousings or under th e
vehicle when you disconnec tth etrailer cable.
!Do no tdisconnec t atrailer wit han engage d
overrun brake .Otherwise ,your vehicle could
be damaged by th ereboundin gof th eoverrun
brake .
XShift th etransmissio nto position P.
XApply thevehicle' selectric parking brake .
XStart theengine.
XClos eth edoors and tailgate.
XApply th etrailer's parking brake .
XDetach thetrailer cable and decoupl eth e
trailer .
XSwitchof fth eengine.
Permissible trailer loads an ddrawbar
loads
Weight specifications
Maximum allowable gross mass
The gross vehicle weight of th etrailer is calcu-
lated by addin gth eweight of th etrailer to th e
weight of th eload and equipmen ton th etrailer .
You will fin dinstallin gdimensions and load s
under "Technical data" (
Ypage 395).
Permissible noseweigh t
You will findinstallin gdimensions and load s
under "Technical data" (Ypage 395).
Loadingatrailer
RWhe nloadin gth etrailer ,mak esur ethat nei-
ther th epermissible gross weight of th etrailer
no rth egross vehicle weight are exceeded.
The permissible gross vehicle weight is indi-
cated on th eidentification plat elocated on
th eB-pilla ron th edriver's sid eof th evehicle.
You can fin dth emaximum permissible values
on th etyp eplates of your vehicle and th e
trailer .Whe ncalculatin ghow muc hweight
th evehicle and trailer may carry, pay atten-
tion to th erespective lowest values.
RThe trailer drawbar load on th eball couplin g
mus tbe adde dto th erea raxl eload to avoid
exceedin gth epermissible gross axl eweight .
The permissible gross vehicle weight is indi-
cated on th eidentification plat elocated on
th eB-pilla ron th edriver's sid eof th evehicle.
iMercedes-Ben zrecommends atrailer load
wher eth etrailer drawbar noseweigh t
accounts fo r 8 %to 15 %of th etrailer's per -
missible gross weight .
iThe weight of additional accessories ,pas-
sengers, and cargo reduce sth epermissible
trailer load and drawbar load fo ryour vehicle.
Checking th evehicle an dtrailer weigh t
RTo checkthat th eweight sof th etowin gvehi-
cl e and th etrailer compl ywit hth emaximum
permissible values, hav eth evehicle/trailer
combination (includin gth edriver ,passen -
gers, and cargo wit h afullylade ntrailer )
weighed on acalibrated weighbridge .
RCheckth egross axl eweight ratin gof th efron t
and rea raxles, th egross weight of th etrailer
and th etrailer drawbar noseweight.
Removin gth eball coupling
XRemov eth esprin gcotter.
XRemov eth ebolt from th eball couplin g
recess .
XRemov eth eball couplin gfrom th eball cou-
plin grecess .
Towing a trailer229
Driving and parking
Z

compressor from the stowage well under-
neath the cargo compartment floor
(
Ypage 339).
XAffix part:of the TIREFIT sticker to the
instrument cluster within the driver's field of
vision.
XAffix part ;of the TIREFIT sticker near the
valve on the wheel with the defective tire.
XPull connector ?with the cable and hose A
out of the tire inflation compressor housing.
XScrew hose Aonto flange Bof tire sealant
bottle :.
XPlace tire sealant bottle :head down into
recess ;of the tire inflation compressor.
XRemove the cap from valve Con the faulty
tire.
XScrew filler hose Donto valve C.
XInsert connector ?into a socket in your vehi-
cle.
Cigarette lighter socket: (
Ypage 312)
12 V sockets: (
Ypage 312)
Observe the notes on the cigarette lighter
(
Ypage 312). Observe the notes on sockets
(Ypage 312).
XTurn the SmartKey to position 1in the igni-
tion lock (Ypage 140).
XPress on and off switch =on the tire inflation
compressor to I.
The tire inflation compressor is switched on.
The tire is inflated.
iFirst, tire sealant is pumped into the tire. The
pressure can briefly rise to approximately
500 kPa (5 bar/73 psi).
Do not switch off the tire inflation com-
pressor during this phase.
XLet the tire inflation compressor run for a
maximum of five minutes. The tire should then
have attained a pressure of at least 180 kPa
(1.8 bar/26 psi).
If a pressure of 180 kPa (1.8 bar/26 psi) has
been attained after five minutes, see "Tire pres-
sure reached" (
Ypage 343).
If a tire pressure of 180 kPa (1.8 bar/26 psi) has
not been attained after five minutes, see "Tire
pressure not reached" (
Ypage 342).
If tire sealant has escaped, clean it off affected
areas as quickly as possible. It is preferable to
use clean water.
If your clothes are soiled with tire sealant, have
them cle aned w
ith perchloroethylene at a dry
cleaner as soon as possible.
Tire pressure not reached
If a pressure of 180 kPa (1.8 bar/26 psi) has not
been attained after five minutes:
XSwitch off the tire inflation compressor.
XUnscrew the filler hose from the valve of the
faulty tire.
Note that tire sealant may escape when you
unscrew the filler hose.
XVery slowly drive forwards or reverse approx- imately 30 ft (10 m).
XPump up the tire again.
After a maximum of five minutes the tire pres-sure must be at least 180 kPa (1.8 bar/
26 psi).
GWARNING
If the required tire pressure is not reached
after the specified time, the tire is too badly
damaged. The tire sealant cannot repair the
tire in this instance. Damaged tires and a tire
pressure that is too low can significantly
impair the vehicle's braking and driving char-
acteristics. There is a risk of accident.
342Flat tire
Breakdown assistance

Do not continue driving. Contact a qualified
specialist workshop.
Tire pressure reached
GWARNING
A tire temporarily sealed with tire sealant
impairs the driving characteristics and is not
suitable for higher speeds. There is a risk of
accident.
You should therefore adapt your driving style
accordingly and drive carefully. Do not exceed the specified maximum speed with a tire that
has been repaired using tire sealant.
The maximum permissible speed for a tire
sealed with tire sealant is 50 mph (80 km/h).
The upper part of the TIREFIT sticker must be
affixed to the instrument cluster in the driver's
field of vision.
!Residue from the tire sealant may come out
of the filler hose after use. This could cause
stains.
Therefore, place the filler hose in the plastic
bag which contained the TIREFIT kit.
HEnvironmental note
Have the used tire sealant bottle disposed of
professionally, e.g. at a qualified specialist
workshop.
If a tire pressure of 180 kPa (1.8 bar/26 psi) has
been attained after five minutes:
XSwitch off the tire inflation compressor.
XUnscrew the filler hose from the valve of the
faulty tire.
XStow the tire sealant bottle and the tire infla-
tion compressor.
XPull away immediately.
XStop after driving for approximately ten
minutes and check the tire pressure with the
tire inflation compressor.
The tire pressure must now be at least
130 kPa (1.3 bar/19 psi).
GWARNING
If the required tire pressure is not reached
after driving for a short period, the tire is too
badly damaged. The tire sealant cannot repair
the tire in this instance. Damaged tires and a
tire pressure that is too low can significantly
impair the vehicle's braking and driving char-
acteristics. There is a risk of accident.
Do not continue driving. Contact a qualified
specialist workshop.
iIn cases such as the one mentioned above,
contact an authorized Mercedes-Benz Cen-
ter. Or call 1-800 FOR-MERCEDES (in the
USA) or 1-800-387-0100 (in Canada).
XCorrect the tire pressure if it is still at least
130 kPa (1.3 ba r/19 psi). See the Tire and
Loading Information placard on the driver's
side B-pillar or the tire pressure table in the
fuel filler flap for values.
XTo increase the tire pressure: switch on the
tire inflation compressor.
XTo reduce the tire pressure: press pressure
release button Eon the filler hose.
XThe tire pressure is shown on pressure gauge
F.
XWhen the tire pressure is correct, unscrew the
filler hose from the valve of the sealed tire.
XScrew the valve cap onto the tire valve of the
sealed tire.
XPull the tire sealant bottle out of the tire infla-
tion compressor.
The filler hose remains attached to the tire
sealant bottle.
XDrive to the nearest qualified specialist work-
shop and have the tire changed there.
XHave the tire sealant bottle replaced as soon
as possible at a qualified specialist workshop.
XHave the tire sealant bottle replaced every
four years at a qualified specialist workshop.
Flat tire343
Breakdown assistance
Z

iJumper cables and further information regarding jump-starting can be obtained at any qualified
specialist workshop.
Towing and tow-starting
Important safety notes
GWARNING
Functions relevant to safety are restricted or
no longer available if:
Rthe engine is not running.
Rthe brake system or the power steering is
malfunctioning.
Rthere is a malfunction in the voltage supply or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely.
GWARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible
gross weight of your vehicle, the:
Rthe towing eye could detach itself
Rthe vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per- missible gross weight of your vehicle.
Details on the permissible gross vehicle weight
of your vehicle can be found on the vehicle iden-
tification plate (
Ypage 385).
!When Active Brake Assist, Distance Pilot
DISTRONIC or the HOLD function is activated,
the vehicle brakes automatically in certain
situations.
To avoid damage to the vehicle, deactivate
these systems in the following or similar sit-
uations:
Rwhen towing the vehicle
Rin the car wash
!Make sure that the electric parking brake is
released. If the electric parking brake is faulty,
visit a qualified specialist workshop.
!Only secure the tow rope or tow bar at the
towing eyes, or the trailer tow hitch, if availa-
ble. You could otherwise damage the vehicle.
!Observe the following points when towing
with a tow rope:
RSecure the tow rope on the same side on
both vehicles.
RMake sure that the tow rope is not longer
than legally permitted. Mark the tow rope in
the middle, e.g. with a white c
loth
(11.8 x 11.8 in). This will make other road
users aware that a vehicle is being towed.
ROnly secure the tow cable to the towing
eyes or, if available, to the trailer tow hitch.
RObserve the brake lamps of the towing
vehicle while driving. Always maintain a dis-
tance a distance so that the tow rope does not sag.
RDo not use steel cables or chains to tow
your vehicle. You could otherwise damage
the vehicle.
!Do not use the trailer tow hitch for recovery
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.
When towing, it is preferable to use a rigid tow-
ing bar as opposed to a tow rope. A rigid towing bar helps to keep the tractive power low.
!When towing away vehicles with KEYLESS-
GO, use the key instead of the Start/Stop
button. The automatic transmission may oth-
erwise shift to position jwhen you open the
driver's or front-passenger door, which could
damage the transmission.
!Do not tow with sling-type equipment. This
could damage the vehicle.
Towing and tow-starting349
Breakdown assistance
Z

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 ofáin (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
(Ypage 339) 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" (
Ypage 340).
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" (
Ypage 375).
Rotating the wheels
GWARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
!On vehicles equipped with a tire pressure
monitor, electronic components are located
in the wheel.
Tire-mounting tools should not be used near
the valve. This could damage the electronic
components.
Only have tires changed at a qualified spe-
cialist workshop.
Always observe the instructions and safety
notes in the "Mounting a wheel" section
(
Ypage 375).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires in
the center.
On vehicles that have the same size front and
rear wheels, you can rotate the wheels accord-
ing to the intervals in the tire manufacturer's
warranty book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3,000 to 6,000 miles (5,000 to
10,000 km). Depending on tire wear, this may
374Changing a wheel
Wheels and tires