engine MERCEDES-BENZ GLS SUV 2018 Repair Manual

SportSporty driving characteris-
tics
Sport PlusParticularly sporty driving
characteristics
SlipperyOptimal driving characteris-
tics on slippery or snow-
covered roads
Additional information for drive programs
(Ypage 151).
Automatic transmission
Important safety notes
GWARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
DIRECT SELECT lever
Overview of transmission positions
jPark position with parking lock
kReverse gear
iNeutral
hDrive
The DIRECT SELECT lever is on the right of the
steering column. The DIRECT SELECT lever always returns to its
original position. The current transmission posi-
tion j,k, iorh is shown on the trans-
mission position display on the multifunction
display (
Ypage 149).
Engaging park position P
!If the engine speed is too high or the vehicle
is coasting, do not shift the automatic trans-
mission directly from htok, from ktoh
or directly to j. Otherwise, the automatic
transmission may be damaged.
XPush the DIRECT SELECT lever switch in the
direction of arrow j.
Engaging park position P automatically
Park positionjis automatically engaged if:
RYou switch off the engine using the SmartKey
and remove the SmartKey
RYou switch off the engine using the SmartKey
or using the Start/Stop button and open the
driver's door or front-passenger door
RYou open the driver's door when the vehicle is
stationary or when driving at a very low speed
and the transmission is in position hork
Under certain conditions, the automatic trans-
mission shifts automatically to transmission
position jif the HOLD function or Distance
Pilot DISTRONIC is activated. Observe the infor-
mation on the HOLD function (
Ypage 187) and
on Distance Pilot DISTRONIC (Ypage 179).
Engaging reverse gear R
!Only move the automatic transmission to
k when the vehicle is stationary.
XIf the transmission is in position hori:
push the DIRECT SELECT lever up past the
first point of resistance.
XIf the transmission is in position j: depress
the brake pedal and push the DIRECT SELECT lever up past the first point of resistance.
148Automatic transmission
Driving and parking

Shifting to neutral N
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
XIf the transmission is in position hork:
push the DIRECT SELECT lever up or down to
the first point of resistance.
XIf the transmission is in position j: depress
the brake pedal and push the DIRECT SELECT
lever up or down to the first point of resist-
ance.
If you switch the engine off with the transmis-
sion in position korh, the automatic trans-
mission shifts to iautomatically.
With the SmartKey: if you then open the driv-
er's door or the front-passenger door or remove
the SmartKey from the ignition lock, the auto-
matic transmission shifts to jautomatically.
With the Start/Stop button: if you then open
the driver's door or the front-passenger door,
the automatic transmission shifts automatically to j.
If you want the automatic transmission to
remain in neutral i, e.g. when having the vehi-
cle cleaned in an automatic, tow-through car
wash: With the SmartKey:
XSwitch on the ignition.
XDepress the brake pedal and keep it
depressed.
XShift to neutral
i.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the SmartKey
in the ignition lock.
With the Start/Stop button:
XRemove the Start/Stop button from the igni-
tion lock.
XInsert the SmartKey into the ignition lock.
XSwitch on the ignition.
XDepress the brake pedal and keep it
depressed.
XShift to neutral i.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the SmartKey
in the ignition lock.
Engaging drive position D
XIf the transmission is in position kori:
push the DIRECT SELECT lever down past the first point of resistance.
XIf the transmission is in position j: depress
the brake pedal and push the DIRECT SELECT lever down past the first point of resistance.
Transmission position and drive pro-
gram display
The current transmission position and drive pro-
gram appear in the multifunction display.
:Transmission position
;Gear
=Drive program
Automatic transmission149
Driving and parking
Z

The arrows in the transmission position display
show how and into which transmission positions
you can shift using the DIRECT SELECT lever.
If the transmission position display on the mul-
tifunction display is not working, you should pull
away carefully to check whether the desired
transmission position is engaged. Ideally, you
should select transmission position hand, in
Mercedes-AMG vehicles, drive program Cor S.
Transmission positions
BPark position
Only shift the transmission into posi-
tion Pwhen the vehicle is stationary
(
Ypage 161). The parking lock
should not be used as a brake when
parking. Always apply the electronic
parking brake in addition to the park-
ing lock in order to secure the vehi-
cle.
If the vehicle electronics are malfunc- tioning, the transmission may be
locked in position P. Have the vehicle
electronics checked immediately at a
qualified specialist workshop.
Park position Pis automatically
engaged if:
Ryou switch off the engine using the
SmartKey and remove the Smart-
Key
Ryou switch off the engine using the
SmartKey or using the Start/Stop
button and open the driver's door
or front-passenger door
Rthe driver's door is opened when
the vehicle is stationary or driving
at very low speed and the trans-
mission is in position Dor R
CReverse gear
Only shift the transmission into posi-
tion Rwhen the vehicle is stationary.
ANeutral
Do not shift the transmission to N
while driving. Otherwise, the auto-
matic transmission could be dam-
aged.
No power is transmitted from the
engine to the drive wheels.
Releasing the brakes will allow you to
move the vehicle freely, e.g. to push
it or tow it.
If ESP
®is deactivated or faulty: shift
the transmission to position Nif the
vehicle is in danger of skidding, e.g.
on icy roads.
If you switch the engine off with the
transmission in position Ror D, the
automatic transmission shifts to N
automatically.
!Coasting in neutral imay
cause damage to the drive train.
7Drive
The automatic transmission changes
gear automatically. All forward gears
are available.
Driving tips
Changing gear
The automatic transmission shifts through the
individual gears automatically when it is in trans-
mission position h. This automatic gear shift-
ing behavior is determined by:
Rthe selected drive program
Rthe position of the accelerator pedal
Rthe road speed
Accelerator pedal position
Your style of driving influences how the auto-
matic transmission shifts gear:
Rlittle throttle: early upshifts
Rmore throttle: late upshifts
150Automatic transmission
Driving and parking

XTo deactivate:press button:.
or
XUse the DYNAMIC SELECT controller to
change the drive program.
Permanent setting (Mercedes-AMG
vehicles)
XTo activate: shift the DIRECT SELECT lever to
position h.
XPress button :.
Indicator lamp ;lights up.
XTo deactivate: press button:.
or
XUse the DYNAMIC SELECT controller to
switch to the Individualdrive program.
Indicator lamp ;goes out.
Shifting gears
!Mercedes-AMG vehicles: the automatic
transmission does not shift up automatically
even when the engine limiting speed for the
current gear is reached. When the engine lim-
iting speed is reached, the fuel supply is cut to
prevent the engine from overrevving. Always
make sure that the engine speed does not
reach the red area of the tachometer. There is
otherwise a risk of engine damage.
XTo shift up: pull steering wheel paddle
shifter ;.
The automatic transmission shifts up to the
next gear.
All vehicles (except Mercedes-AMG vehi-
cles): if the maximum engine speed in the
gear currently engaged is reached and you
continue to accelerate, the automatic trans-
mission automatically shifts up to prevent
engine damage.
XTo shift down: pull steering wheel paddle
shifter :.
The automatic transmission shifts down to
the next gear.
Automatic down shifting occurs when coast-
ing.
If the engine were to exceed the maximum
engine speed when shifting down, the auto-
matic transmission protects against engine
damage by not shifting down.
Shift recommendation
The gearshift recommendations assist you in
adopting an economical driving style. The rec-
ommended gear is shown in the multifunction
display.
XWhen the corresponding gearshift recom-
mendation :appears in the multifunction
display of the instrument cluster, shift to rec-
ommended gear ;.
Automatic transmission153
Driving and parking
Z

Upshifting (Mercedes-AMG vehicles)
!In manual mode, the automatic transmis-
sion does not shift up automatically even
when the engine limiting speed for the current
gear is reached. When the engine limiting
speed is reached, the fuel supply is cut to
prevent the engine from overrevving. Always
make sure that the engine speed does not
reach the red area of the tachometer. There is
otherwise a risk of engine damage.
:Gear indicator
;Upshift indicator
Before the engine speed reaches the red area,
an upshift indicator will be shown in the multi-
function display.
XWhen the UPmessage appears in the multi-
function display, pull on the right-hand steer-
ing wheel paddle shifter.
Kickdown
Mercedes-AMG vehicles: kickdown is only
possible in the temporary setting.
XFor maximum acceleration, depress the
accelerator pedal beyond the pressure point.
The automatic transmission shifts to a lower
gear depending on the engine speed.
XShift back up once the desired speed is
reached.
During kickdown, you cannot shift gears using
the steering wheel paddle shifters.
If you apply full throttle, the automatic trans-
mission shifts up to the next gear when the
maximum engine speed is reached. This pre-
vents the engine from overrevving.
154Automatic transmission
Driving and parking

Problems with the transmission
ProblemPossible causes/consequences andMSolutions
The transmission has
problems shifting gear.The transmission is losing oil.
XHave 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 intosecondgear and reverse gear.
XStop the vehicle.
XShift the transmission to position P.
XSwitch off the engine.
XWait at least ten seconds before restarting the engine.
XShift the transmission to positionDor R.
If D is selected, the transmission shifts into secondgear; ifRis
selected, the transmission shifts into reverse gear.
XHave 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.
XStop the vehicle.
XShift the transmission to position P.
XSwitch off the engine.
XWait at least ten seconds before restarting the engine.
XShift the transmission to positionDor R.
XHave 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 0or 1or Start/Stop
button in position 0or 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
GWARNING
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.
Refueling155
Driving and parking
Z

GWARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that fuel does not come into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
RWash away fuel from skin immediately
using soap and water.
RIf fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance with-
out delay.
RIf fuel is swallowed, seek medical assis-
tance without delay. Do not induce vomit-
ing.
RImmediately change out of clothing which
has come into contact with fuel.
GWARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the vehicle body before opening
the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged.
GWARNING
Vehicles with a diesel engine:
If you mix diesel fuel with gasoline, the flash
point is lower than that of pure diesel fuel.
When the engine is running, exhaust system
components could overheat without being
noticed. There is a risk of fire.
Never refuel with gasoline. Never mix gasoline with diesel fuel.
!Do not use gasoline to refuel vehicles with a
diesel engine. Do not switch on the ignition if
you accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel system. Even small amounts of the wrong fuel could
result in damage to the fuel system and the engine. The repair costs are high. Notify a
qualified specialist workshop and have the
fuel tank and fuel lines drained completely.
!Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the ignition
if you accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel system. Even small amounts of the wrong fuel could
result in damage to the fuel system and the
engine. Notify a qualified specialist workshop
and have the fuel tank and fuel lines drained
completely.
!Overfilling the fuel tank could damage the
fuel system.
!Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
!Use a filter when adding fuel from a fuel can.
The fuel lines and/or the fuel injection system
could otherwise be blocked by particles from
the fuel can.
Do not get into the vehicle again during the refu-
eling process. Otherwise, electrostatic charge
could build up again.
If you overfill the fuel tank, fuel could spray out
when the fuel pump nozzle is removed.
For further information on fuel and fuel quality
(
Ypage 387).
Refueling
General information
Pay attention to the important safety notes
(Ypage 155).
The fuel filler flap is unlocked or locked auto-
matically when you unlock or lock the vehicle
with the SmartKey or using KEYLESS-GO.
The position of the fuel filler cap is displayed
8 in the instrument cluster. The arrow next
to the filling pump indicates the side of the vehi-
cle.
156Refueling
Driving and parking

Opening the fuel filler flap
:To open the fuel filler flap
;To insert the fuel filler cap
=Instruction label for fuel type to be refueled
?Tire pressure table
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, on vehicles with KEYLESS ‑GO:
XOpen the driver's door.
The vehicle electronics are now in key posi-
tion u. This is the same as the key having
been removed.
The driver’s door can be closed again.
XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap swings up.
XTurn the fuel filler cap counterclockwise and
remove it.
XInsert the fuel filler cap into the holder
bracket on the inside of filler flap ;.
XCompletely insert the filler neck of the fuel
pump nozzle into the tank, hook in place and
refuel.
XOnly fill the tank until the pump nozzle
switches off.
Do not add any more fuel after the pump stops
filling for the first time. Otherwise, fuel may leak
out.
Vehicles with a diesel engine: the filler neck is
designed for refueling at diesel filling pumps.
Closing the fuel filler flap
XReplace the cap on the filler neck and turn
clockwise until it engages audibly.
XClose the fuel filler flap.
Close the fuel filler flap before locking the vehi-
cle.
If you are driving with the fuel filler cap open, the
8 reserve fuel warning lamp flashes. A mes-
sage appears in the multifunction display
(
Ypage 263).
In addition, the ;Check Engine warning
lamp may light up (
Ypage 288).
Refueling157
Driving and parking
Z

Problems with fuel and the fuel tank
ProblemPossible causes/consequences andMSolutions
Fuel is leaking from the
vehicle.GWARNING
The fuel line or the fuel tank is faulty.
Risk of explosion or fire.
XApply the electric parking brake.
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, on vehicles with KEYLESS‑GO:
XOpen the driver's door.
The vehicle electronics are now in key position u. This is the same
as the SmartKey having been removed.
XDo not restart the engine under any circumstances.
XConsult a qualified specialist workshop.
The engine does not
start.The fuel tank of a vehicle with a diesel engine has been run completely
dry.
XRefuel the vehicle with at least 5.3 US qt (5 liters) of diesel.
XTurn the ignition on for approximately ten seconds (Ypage 140).
XStart the engine continuously for up to ten seconds until it runs
smoothly.
If the engine does not start:
XTurn the ignition on again for approximately ten seconds
(Ypage 140).
XStart the engine again continuously for up to ten seconds until it
runs smoothly.
If the engine does not start after three attempts:
XConsult a qualified specialist workshop.
The fuel filler flap cannot
be opened.The fuel filler flap is not unlocked.
XUnlock the vehicle (Ypage 77).
The SmartKey battery is discharged or nearly discharged.
XUnlock the vehicle using the mechanical key (Ypage 79).
The fuel filler flap is unlocked, but the opening mechanism is jammed.
XConsult a qualified specialist workshop.
DEF (BlueTEC vehicles only)
General notes
To function properly, BlueTEC exhaust gas after-
treatment must be operated with the reducing
agent DEF. Adding DEF is one of the tasks per-
formed during maintenance. When the supply of DEF is almost used up, the
Check Additive See Operator's Manual
message is shown in the multifunction display.
If you drive the vehicle faster than 10 mph
(16 km/h), the
Check Additive See Opera‐
tor's Manualmessage goes out after approx-
imately one minute.
158Refueling
Driving and parking

When the DEF supply drops to a minimum, the
Remaining Starts: 16message is shown in
the multifunction display.
If the Remaining Starts: 16
message
appears in the multifunction display, you can
start the engine another 16 times. If DEF is not
refilled, you will subsequently be unable to
start the engine.
XAdd at least 2 gal (7.5 l)of DEF.
XSwitch on the ignition for at least 60 seconds.
XStart the engine.
iHave the DEF tank refilled at a qualified spe-
cialist workshop.
Use the special DEF refill bottle when adding
DEF between maintenance intervals. You can
obtain further information from an authorized
Mercedes-Benz Center or, if necessary, contact
Roadside Assistance (
Ypage 29).
If the outside temperature is below 12 ‡
(Ò11 †), it may be difficult to top up. If DEF is
frozen and there is an active warning indicator, it
may not be possible to add DEF. Park the vehicle
in a warmer place, e.g. in a garage, until DEF has become fluid again. It will then be possible to
add DEF again. Alternatively, have the DEF tank
refilled at a qualified specialist workshop.
Further information about BlueTEC exhaust gas
aftertreatment and DEF is available at any
authorized Mercedes-Benz Center.
Important safety notes
DEF is a water-soluble fluid for the exhaust gas
aftertreatment of diesel engines. It is:
Rnot poisonous
Rcolorless and odorless
Rnot flammable
When you open the DEF container, small
amounts of ammonia vapor may be released.
Ammonia vapors have a pungent odor and are
particularly irritating to the skin, to mucous
membranes and to the eyes. You may experi-
ence a burning sensation in your eyes, nose and
throat. Coughing and watering of the eyes are
possible.
Do not inhale ammonia vapors. Fill the DEF tank
only in well-ventilated areas.
DEF must not come into contact with your skin,
eyes or clothing and must not be swallowed.
Keep DEF away from children. If you or other persons come into contact with
DEF, observe the following:
RRinse DEF from your skin immediately with
soap and water.
RIf DEF comes into contact with your eyes,
immediately rinse them thoroughly with clean
water. Seek medical assistance without
delay.
RIf DEF has been swallowed, rinse your mouth
out immediately. Drink plenty of water. Seek
medical assistance without delay.
RChange out of clothing contaminated with
DEF immediately.
!Only use DEF in accordance with
ISO 22241. Do not mix any additives with
DEF, and do not dilute DEF with water. This
may destroy the BlueTEC exhaust gas after-
treatment system.
!The vehicle must be parked on level ground
to fill the DEF tank. The DEF tank can only be
filled as intended with the vehicle parked on a level surface. This avoids false level readings.
Filling the tank is not permitted if the vehicle
is not parked on a level surface. There is a
danger of overfilling, which could result in
damage to components of the BlueTEC
exhaust gas aftertreatment.
!Immediately rinse off surfaces which come
into contact with DEF or remove DEF with a
damp cloth and cold water. If DEF has already
crystallized, clean using a sponge and cold
water. DEF residue crystallizes after a short
period and contaminates the affected surfa-
ces. Furthermore, electrical components in
the vicinity may be damaged by DEF.
!DEF is not a fuel additive and must not be
added to the fuel tank. If DEF is added to the
fuel tank, this can lead to engine damage.
For further information on DEF, see
(
Ypage 389).
Refueling159
Driving and parking
Z