2017 MERCEDES-BENZ GLS-Class SUV tow bar

XSecure the bolt using spring cotterB.
XCheck the ball coupling, bolt and spring cotter
for correct installation.
If the ball coupling cannot be correctly mounted,
remove the ball coupling. Under these circum-
stances, the ball coupling must not be used for
trailer towing.
Have the entire trailer tow hitch checked at a
qualified specialist workshop.
Coupling up a trailer
!
Do not connect the trailer's brake system (if
featured) to the hydraulic brake system of the
towing vehicle, as the latter is equipped with
an anti-lock brake system. Doing so will result
in a loss of function of the brake systems of
both the vehicle and the trailer.
XShift the transmission to position P.
XApply the vehicle's electric parking brake.
XStart the engine.
XVehicles with AIRMATIC package: select
normal level and the Comfortdrive program.
XSwitch off the engine.
XClose the doors and tailgate.
XCouple up the trailer.
XEstablish the electrical connection between
the vehicle and the trailer.
XCheck that the trailer lighting system is work-
ing.
XPush the combination switch upwards/down-
wards and check whether the corresponding
turn signal on the trailer flashes.
A trailer that is connected is recognized only
when the electrical connection is established
correctly and when the lighting system is work-
ing properly. The function of other systems also
depends on this, for example:
RESP®
RParking Assist PARKTRONIC
RParking Pilot
RActive Blind Spot Assist
RActive Lane Keeping Assist
iVehicles with the AIRMATIC package: if you
couple up a trailer, the vehicle always remains
at normal level. When coupling up a trailer,
please observe the foll
owing:
RIf the normal level has not been set man-
ually, the vehicle is automatically lowered
to normal level. This is the case if a speed of
5 mph (8 km/h) is reached.
RThe
Sport drive program is not available.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Observe the maximum permissible trailer
dimensions (width and length).
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 switch applies the
trailer brakes.
Towing a trailer225
Driving and parking
Z

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
tra
iler 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 toutilize 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-conditioning 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.
Decoupling a trailer
GWARNING
If you uncouple a trailer with the overrun
brake engaged, you could trap your hand
between the vehicle and the trailer drawbar.
There is a risk of injury.
Do not uncouple a trailer if the overrun brake
is engaged.
GWARNING
Vehicles with level control:
The vehicle is lowered as soon as you discon-
nect the trailer cable. This could result in your
limbs or those of other people that are
between the vehicle body and tires or under-
226Towing a trailer
Driving an d parking

neath the vehicle being trapped. There is a
risk of injury.
Make sure that nobody is in the immediate
vicinity of the wheel housings or under the
vehicle when you disconnect the trailer cable.
!Do not disconnect a trailer with an engaged
overrun brake. Otherwise, your vehicle could
be damaged by the rebounding of the overrun brake.
XShift the transmission to position P.
XApply the vehicle's electric parking brake.
XStart the engine.
XClose the doors and tailgate.
XApply the trailer's parking brake.
XDetach the trailer cable and decouple the
trailer.
XSwitch off the engine.
Permissible trailer loads and drawbar
loads
Weight specifications
Maximum allowable gross mass
The gross vehicle weight of the trailer is calcu-
lated by adding the weight of the trailer to the
weight of the load and equipment on the trailer. You will find installing dimensions and loads
under "Technical data" (
Ypage 387).
Permissible noseweight
You will find installing dimensions and loads
under "Technical data" (Ypage 387).
Loading a trailer
RWhen loading the trailer, make sure that nei-
ther the permissible gross weight of the trailer
nor the gross vehicle weight are exceeded.
The permissible gross vehicle weight is indi-
cated on the identification plate located on
the B-pillar on the driver's side of the vehicle.
You can find the maximum permissible values
on the type plates of your vehicle and the
trailer. When calculating how much weight the vehicle and trailer may carry, pay atten-
tion to the respective lowest values.
RThe trailer drawbar load on the ball coupling
must be added to the rear axle load to avoid
exceeding the permissible gross axle weight.
The permissible gross vehicle weight is indi-
cated on the identification plate located on
the B-pillar on the driver's side of the vehicle.
iMercedes-Benz recommends a trailer load
where the trailer drawbar noseweight
accounts for 8 % to 15 % of the trailer's per-
missible gross weight.
iThe weight of additional accessories, pas-
sengers, and cargo reduces the permissible
trailer load and drawbar load for your vehicle.
Checking the vehicle and trailer weight
RTo check that the weights of the towing vehi-
cle and the trailer comply with the maximum
permissible values, have the vehicle/trailer
combination (including the driver, passen-
gers, and cargo with a fully laden trailer)
weighed on a calibrated weighbridge.
RCheck the gross axle weight rating of the front and rear axles, the gross weight of the trailer
and the trailer drawbar noseweight.
Removing the ball coupling
XRemove the spring cotter.
XRemove the bolt from the ball coupling
recess.
XRemove the ball coupling from the ball cou-
pling recess.
XClean the ball coupling if it is dirty.
XStow the ball coupling so that it cannot be
thrown around.
Observe the loading guidelines (
Ypage 294)
and the safety notes regarding stowage spaces
(
Ypage 294).
Information on cleaning and care of the trailer
tow hitch (
Ypage 329).
Trailer power supply
!
Accessories with a maximum power con-
sumption of 180 W can be connected to the
permanent power supply.
Towing a trailer227
Driving an d parking
Z

compressor from the stowage well under-
neath the cargo compartment floor
(
Ypage 331).
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 downwards
into recess ;of the tire inflation compres-
sor.
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 306)
12 V sockets: (
Ypage 306) Observe the notes on the cigarette lighter
(
Ypage 306). Observe the notes on sockets
(Ypage 306).
XTurn the SmartKey to position 1in the ignition
lock (Ypage 138).
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 335).
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 334).
If tire sealant has escaped, clean it off affected
areas as quickly as possible. Use plain water if
possible.
If your clothes are soiled with tire sealant, have
them cleaned wi th p
erchloroethylene 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
334Flat tire
Breakdown assistance

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.
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 bar/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.
Flat tire335
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 377).
!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.
REnsure that the tow cable is not longer than legally permitted. Mark the tow cable in the
middle, e.g. with a white c
loth
(30x30 cm).
This will make other road users aware that
the vehicle is being towed.
ROnly secure the tow cable to the towing
eye.
RObserve the brake lamps of the towing
vehicle while driving. Always maintain a dis-
tance 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 vehicles with KEYLESS-GO,
use the key instead of the Start/Stop button.
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.
Towing and tow-starting341
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 331) 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 332).
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 367).
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 367).
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
366Changing a wheel
Wheels and tires

Accelerate carefully and make sure that the
wheels do not spin when driving on steep ter-
rain.
iIf the load on the front axle is reduced when
pulling away on a steep uphill slope, the front
wheels have a tendency to spin. 4ETS recog-
nizes this and brakes the wheels accordingly.
The rear wheel torque is increased, making it
easier to drive off.
For further information about the maximum gra-
dient climbing ability, see (
Ypage 171).
Trailer tow hitch
Mounting dimensions
!
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.
:Anchorage points for the trailer tow hitch
;Rear axle center line
Trailer loads
Trailer loads, trailer drawbar nose-
weights and axle loads
Missing values were not available at the time of going to print.
GLS 450 4M ATIC,
GLS 550 4M ATIC and
GLS 350 d 4 MATIC
Permissible trailer load,
braked (at a minimum gra-
dient-climbing capability
of12%from a standstill)7500 lbs
(3402 kg)
Maximum drawbar nose-
weight (the drawbar nose-
weight is not included in
the trailer load)600 lbs
(272 kg)
Gross rear axle weight rat-
ing when towing a trailer3968 lbs
(1800 kg)
Mercedes ‑A
MG GLS 63 4 MATIC
Permissible trailer load,
braked (at a minimum gra-
dient-climbing capability
of12%from a standstill)
Maximum drawbar nose-
weight (the drawbar nose-
weight is not included in
the trailer load)
Gross rear axle weight rat-
ing when towing a trailer
The actual noseweight may not be higher than
the value which is given. The value can be found
on the trailer tow hitch or trailer identification
plates. The lowest weight applies.
The maximum permissible trailer drawbar nose-
weight is the maximum weight with which the
trailer drawbar can be loaded. Limit for
Mercedes-Benz-approved trailer couplings.
Trailer tow hitch387
Technical data
Z