2018 MERCEDES-BENZ GLS oil

Problems with the transmission Problem
Possible causes/consequences and P Solutions
The transmission has
problems shifting gear. The transmission is losing oil. X
Have the transmission checked at a qualified specialist workshop
immediately.
7G-TRONIC:
The acceleration ability
is deteriorating.
The transmission no lon-
ger changes gear. The transmission is in emergency mode.
It is only possible to shift into second gear and reverse gear.X
Stop the vehicle. X
Shift the transmission to position P .X
Switch off the engine. X
Wait at least ten seconds before restarting the engine. X
Shift the transmission to position D or R .
If D is selected, the transmission shifts into second gear; if R is
selected, the transmission shifts into reverse gear. X
Have the transmission checked at a qualified specialist workshop
immediately.
9G-TRONIC:
The acceleration ability
is deteriorating.
The transmission no lon-
ger changes gear. The transmission is in emergency mode.
It is only partly possible to engage the gears or the transmission is in
position N . X
Stop the vehicle. X
Shift the transmission to position P .X
Switch off the engine. X
Wait at least ten seconds before restarting the engine. X
Shift the transmission to position D or R .X
Have the transmission checked at a qualified specialist workshop
immediately.
Transfer case This section is only valid for vehicles with 4-
wheel drive (4MATIC). Power is always trans-
mitted to both axles.
! Performance tests may only be carried out
on a 2-axle dynamometer. The brake system
or transfer case could otherwise be damaged.
Contact a qualified specialist workshop for a
performance test.
! Because ESP ®
is an automatic system, the
engine and ignition must be switched off
(SmartKey in position 0 or 1 or Start/Stop
button in position 0 or 1 ) when the electric
parking brake is being tested on a brake dyna-
mometer (maximum 10 seconds).
Braking triggered automatically by ESP ®
may
seriously damage the brake system. ! Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised, as
doing so will damage the transmission.
Refueling
Important safety notes
G WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before
refueling. Refueling 155
Driving and parking Z

For more information on driving with summer
tires, see ( Y
page 356).
Observe the notes in the "Changing a wheel"
section ( Y
page 374).
Off-road driving
Important safety notes
G WARNING
If you drive on a steep incline at an angle or
turn when driving on an incline, the vehicle
could slip sideways, tip and rollover. There is a
risk of an accident.
Always drive on a steep incline in the line of
fall (straight up or down) and do not turn the
vehicle.
G WARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with
hot parts of the exhaust system. There is a risk
of fire.
When driving off road or on unpaved roads,
check the vehicle's underside regularly. In
particular, remove parts of plants or other
flammable materials which have become
trapped. In the case of damage, contact a
qualified specialist workshop.
G WARNING
If the vehicle level is high, the vehicle center of
gravity is raised. This could cause the vehicle
to tip over more easily on uphill or downhill
gradients. There is a risk of an accident.
Select the lowest possible vehicle level.
! There is a risk of damage to the vehicle if: R
the vehicle becomes stuck, e.g. on a high
curb or an unpaved road R
you drive too fast over an obstacle, e.g. a
curb, a speed bump or a pothole in the road R
a heavy object strikes the underbody or
parts of the chassis
In situations like this, the body, the under-
body, chassis parts, wheels or tires could be
damaged without the damage being visible. Components damaged in this way can unex-
pectedly fail or, in the case of an accident, no
longer withstand the loads they are designed
to.
If the underbody paneling is damaged, com-
bustible materials such as leaves, grass or
twigs can gather between the underbody and
the underbody paneling. If these materials
come in contact with hot parts of the exhaust
system, they can catch fire.
In such situations, have the vehicle checked
and repaired immediately at a qualified spe-
cialist workshop. If on continuing your jour-
ney you notice that driving safety is impaired,
pull over and stop the vehicle immediately,
paying attention to road and traffic condi-
tions. In such cases, consult a qualified spe-
cialist wor kshop.
W hen
driving off-road, substances such as sand,
mud and water or water mixed with oil may get
into the brakes. This could result in a reduced
braking effect or in total brake failure and also in
increased wear and tear. The braking charac-
teristics change depending on the material
entering the brakes. Clean the brakes after driv-
ing off-road. If you detect a reduced braking
effect or grinding noises, have the brake system
checked in a qualified specialist workshop as
soon as possible. Adapt your driving style to the
different braking characteristics.
Driving off-road increases the likelihood of dam-
age to the vehicle, which, in turn, can lead to
failure of the mechanical assembly or systems.
Adapt your driving style to suit the terrain con-
ditions. Drive carefully. Have damage to the
vehicle rectified immediately at a qualified spe-
cialist workshop.
Do not switch to transmission position N when
driving off-road. If you try to brake the vehicle
using the service brake, you could lose control
of the vehicle. If the gradient is too steep for your
vehicle, drive back down in reverse gear.
General notes
H Environmental note
Protection of the environment is of primary
importance. Treat nature with respect.
Observe all prohibiting signs.
Read this section carefully before driving your
vehicle off-road. Practice by driving over more
gentle off-road terrain first.170
Driving tips
Driving and parking

Familiarize yourself with the characteristics of
your vehicle and the gear shift operation before
driving through difficult terrain.
The following driving systems are specially
adapted to off-road driving: R
the Off-road drive program (vehicles without
Off-Road Engineering package)
( Y
page 219) R
Off-road and Off-road Plus drive programs
(vehicles with Off-Road Engineering package)
( Y
page 220) R
LOW RANGE off-road gear (vehicles with the
Off-Road Engineering package)
( Y
page 221) R
Differential lock (vehicles with the Off-Road
Engineering package) ( Y
page 221)R
Off-road ABS ( Y
page 67)R
Off-road 4ETS ( Y
page 70)R
Off-road ESP ®
( Y
page 71)R
AIRMATIC package (vehicle level)
( Y
page 188) R
DSR (Downhill Speed Regulation)
( Y
page 218)
Observe the following notes: R
Stop the vehicle before starting to drive along
an off-road route. If necessary, select the off-
road program ( Y
page 220) or shift to the
LOW RANGE off-road gear ( Y
page 221).R
Select a vehicle level that is suitable for the
terrain. To avoid damaging the vehicle, make
sure there is always sufficient ground clear-
ance. R
Check that items of cargo and loads are
stowed safely and are well secured
( Y
page 305). R
Always keep the engine running and in gear
when driving on a downhill gradient. Activate
DSR ( Y
page 218).R
Always keep the engine running and in gear
when driving down an incline. R
Adapt your speed to the terrain. The rougher,
steeper or more ruts on the terrain, the slower
your speed should be. R
Do not jump with the vehicle as this will inter-
rupt the vehicle's propulsion. R
Drive with extreme care on unfamiliar off-road
routes where visibility is poor. For safety rea-
sons, get out of the vehicle first and survey
the off-road route. R
Look out for obstacles, such as rocks, holes,
tree stumps and furrows. R
Take care when turning on an uphill or down-
hill slope or when driving across a slope. The
vehicle could otherwise tip over. R
Always keep the doors, the tailgate, the side
windows and the sliding sunroof closed while
the vehicle is in motion. R
Do not shift the automatic transmission to
position \\ . R
Observe the notes on off-road fording
( Y
page 169).
i Information about retrofitting special all-ter-
rain tires is available from any qualified spe-
cialist workshop.
i Do not use the HOLD function when driving
off-road, on steep uphill or downhill gradients
or on slippery or loose surfaces. The HOLD
function cannot hold the vehicle on such sur-
faces.
Checklist before driving off-road
! If the engine oil warning lamp lights up while
the vehicle is in motion, stop the vehicle in a
safe place as soon as possible. Check the
engine oil level. The engine oil warning lamp
warning must not be ignored. Continuing the
journey while the symbol is displayed could
lead to engine damage. X
Engine oil level: check the engine oil level
and add oil if necessary.
When driving on steep gradients, the engine
oil level must be sufficiently high to ensure a
correct oil supply in the vehicle. X
DEF tank (BlueTEC vehicles): check the
level and add if necessary ( Y
page 158).X
Tire-changing tool kit: check that the jack is
working and make sure you have the lug
wrench, a robust tow cable and a folding
spade in the vehicle. X
Wheels and tires: check the tread depth and
pressure of the tires. X
Check for damage and remove any foreign
objects, e.g. small stones, from the wheels/
tires. X
Replace any missing valve caps. X
Replace dented or damaged wheels. X
Rims: dented or bent rims can result in a loss
of tire pressure and damage the tire bead. Driving tips 171
Driving and parking Z

If the multifunction display shows oil temper-
ature

Engine compartment
Hood
Important safety notes
G WARNING
If the hood is unlatched, it may open up when
the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. Before
every trip, ensure that the hood is locked.
G WARNING
When opening and closing the hood, it may
suddenly fall into the closed position. There is
a risk of injury to persons within range of
movement of the hood.
Open and close the hood only when no one is
within its range of movement.
G WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
G WARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There
is a risk of injury.
If you need to do any work inside the engine
compartment: R
switch off the ignition R
never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area R
remove jewelry and watches R
keep items of clothing and hair, for exam-
ple, away from moving parts
G WARNING
The ignition system and the fuel injection sys-
tem work under high voltage. If you touch
components which are under voltage, you
could get an electric shock. There is a risk of
injury.
Never touch components of the ignition sys-
tem or fuel injection system when the ignition
is switched on.
Electrically live components include ignition
coils, spark plug connectors and the test socket.
Opening the hood
G WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following.
G WARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
! Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield wip-
ers or the hood.Engine compartment 325
Maintenance and care Z

X
Make sure that the windshield wipers are
turned off. X
Pull release lever C on the hood.
The hood is released.
X
Reach into the gap, pull hood catch handle D
up and lift the hood.
If you lift the hood by approximately 15 in
(40 cm), the hood is opened and held open
automatically by the gas-filled strut.
Closing the hood X
Lower the hood and let it fall from a height of
approximately 8 in (20 cm). X
Check that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close it
with a little more force.
Radiator
Vehicles with a diesel engine: do not cover
the radiator. such as with a thermal mat or
insect protection cover. Otherwise, the values of
the European on-board diagnostics may be
affected. Some of these readings are required
by law and must be accurate at all times. Engine oil
Important safety notes
G WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following.
G WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
G WARNING
If engine oil comes into contact with hot com-
ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil is not spilled next to
the filler neck. Let the engine cool down and
thoroughly clean the engine oil off the com-
ponents before starting the engine.
General notes Depending on your driving style, the vehicle
consumes up to 0.9 US qt (0.8 liters) of oil per
600 miles (1,000 km). The oil consumption may
be higher than this when the vehicle is new or if
you frequently drive at high engine speeds.
Depending on the engine, the oil dipstick may be
in a different location.326
Engine compartment
Maintenance and care

When checking the oil level: R
park the vehicle on a level surface. R
the engine should be switched off for approx-
imately five minutes if the engine is at normal
operating temperature. R
if the engine is not at normal operating tem-
perature, e.g. if the engine was only started
briefly, wait about 30 minutes before carrying
out the measurement.
Checking the oil level using the oil dip-
stick
Example: vehicles with a gasoline engine
Example: vehicles with a diesel engine X
Pull oil dipstick C out of the dipstick tube.X
Wipe off oil dipstick C .X
Slowly slide oil dipstick C into the guide tube
to the stop, and take it out again.
If the level is between MIN mark

Further information on engine oil ( Y
page 389).
Additional service products
Important safety notes
G WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following.
G WARNING
The cooling system is pressurized, particularly
when the motor is warm. If you open the cap,
you could be scalded if hot coolant sprays out.
There is a risk of injury.
Let the engine cool down before you open the
cap. Wear gloves and eye protection. Slowly
open the cap to relieve pressure.
The coolant level may only be checked and cool-
ant refilled when the engine and engine cooling
system have cooled down.
G WARNING
Windshield washer concentrate could ignite if
it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck. Checking coolant level X
Park the vehicle on a level surface.
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down. X
Turn the SmartKey to position H in the igni-
tion lock ( Y
page 140).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y
page 142).X
Check the coolant temperature gauge in the
multifunction display.
The coolant temperature must be below
158 ‡ (70 †). X
Turn the SmartKey to position in the ignition
lock