2012 MERCEDES-BENZ GL-Class overheating

Driving tips
Kickdown
Use kickdown for maximum acceleration.
XVehicles for USA: fully depress the
accelerator pedal.
The transmission shifts to a lower gear
depending on the engine speed.XVehicles for Canada: depress the
accelerator pedal beyond the pressure
point.
The transmission shifts to a lower gear
depending on the engine speed.
Rocking the vehicle free
Rocking the vehicle free by shifting back and
forth between transmission positions D and
R can help to free a vehicle that has become
stuck in mud or snow. The engine
management system of the vehicle limits
shifting back and forth between transmission
positions D and R to a maximum speed of
5 mph (9 km/h). To shift back and forth
between transmission positions D and R,
move the selector lever up and down beyond
the pressure point.
Working on the vehicle
GWARNING
When working on the vehicle, engage the
parking brake and shift the automatic
transmission into park position P. Otherwise
the vehicle could roll away which could result
in an accident and/or serious personal injury.
Trailer towing
XWhen towing a trailer and driving downhill,
shift to the lower gear if the automatic
transmission constantly shifts between
two gears.XEngaging a lower gear and reducing the
speed reduces the risk of the engine
overheating.Steering wheel paddle shifters:Left-hand steering wheel paddle shifter;Right-hand steering wheel paddle shifter
You can restrict or derestrict the shift range
by using the steering wheel paddle shifters.
Shift ranges
Introduction
When the automatic transmission is in
position D, it is possible to restrict or
derestrict the shift range ( Y page 157).
The shift range selected is shown in the
multifunction display. The automatic
transmission shifts only as far as the selected
gear.
Driving situations=You can use the engine's braking
effect.5To use the braking effect of the
engine on downhill gradients and
for driving:
R on steep mountain roads
R in mountainous terrain
R in arduous conditions4To use the braking effect of the
engine on extremely steep downhill
gradients and on long downhill
stretchesAutomatic transmission157Driving and parkingZ

to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.GWARNING
Do not fill diesel tanks with gasoline. Do not
mix diesel fuel with gasoline. Otherwise the
fuel system and engine could be damaged. In
addition, the vehicle could catch fire.
! Do not use gasoline to refuel vehicles with
a diesel engine. Do not use diesel to refuel
vehicles with a gasoline engine. Even a
small quantity of the wrong fuel will
damage the fuel system and engine.
! Do not switch on the ignition if you
accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel lines.
Notify a qualified specialist workshop and
have the fuel tank and fuel lines drained
completely.
Gasoline
Fuel grade
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection
system could be blocked by particles from
the fuel can.
i Only refuel with premium-grade unleaded
gasoline with a specified minimum octane
number of 91 (average value of 96 RON/
86 MON).
Usually, you will find information about the
fuel grade on the pump. If you cannot find
the label on the gasoline pump, ask the gas
station staff.
You can find more information under “Fuel”
( Y page 372), or by contacting an
authorized Mercedes-Benz Service Center
or visiting http://www.mbusa.com (USA
only).
Diesel
Fuel grade
! Only refuel with ULTRA-LOW SULFUR
DIESEL FUEL (ULSD, 15 ppm SULFUR
MAXIMUM). Using other diesel fuels could
result in increased wear and damage to the
engine and/or exhaust system.
Never refuel with marine diesel or heating
oil.
Do not mix these fuels with diesel fuels and
do not use any special additives, as this
may result in damage.
! Use a filter when adding fuel from a fuel
can. Otherwise, the fuel lines and/or the
fuel injection system could be blocked by
particles from the fuel can.
i Usually, you will find information about
the fuel grade on the pump. If you cannot
find the label on the gasoline pump, ask the
gas station staff.
You can find more information under “Fuel”
( Y page 372), or by contacting an
authorized Mercedes-Benz Service Center
or visiting http://www.mbusa.com (USA
only).
Low outside temperatures
! Do not use gasoline to refuel vehicles with
a diesel engine. Never mix diesel with
gasoline or kerosene, as this may result in
damage to the engine or fuel system.
Diesel fuel with improved cold flow properties
is available during the winter months. Further
information on fuel properties can be
160RefuelingDriving and parking

Exhaust checkGWARNING
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the engine in confined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work at peak efficiency
when they are maintained exactly in
accordance with the manufacturer's
specifications. For this reason, all work on the
engine must be carried out only by qualified
and authorized Mercedes-Benz technicians.
The engine settings must not be changed in
any circumstances. Furthermore, all specific
service work must be carried out at regular
intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Service Booklet.
Engine oil
! Vehicles with a diesel particle filter:
If the vehicle is mostly driven for short
distances, it is possible that malfunctions
may occur during the automatic cleaning of
the diesel particle filter. This can lead to
engine damage. Therefore, if you frequently
drive short distances, make sure to drive
on highways or inter-urban roads for 20
minutes at least every 310 miles (500 km).
Brakes
Important safety notesGWARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of control loss.
Do not engage the transfer case in position
LOW when driving on ice or packed snow. At
speeds below 18 mph (30 km/h) vehicle
steering is adversely affected by the Off-road
ABS.
GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
Downhill gradients
! On long and steep gradients, you must
reduce the load on the brakes by shifting
early to a lower gear. This allows you to take
advantage of the engine braking effect and
helps avoid overheating and excessive
wear of the brakes.
When you take advantage of the engine
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road
surface. This could cause damage to the
drive train. This type of damage is not
covered by the Mercedes-Benz warranty.
Heavy and light loads
GWARNING
Depressing the brake pedal constantly results
in excessive and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately, but
Driving tips169Driving and parkingZ

GWARNING
Never turn the vehicle around on steep inclines. The vehicle might roll over. If the vehicle cannot
complete the attempted climb, back it down in reverse gear.
i Hill start assist will aid you when pulling away on a hill.
For more information, see "Hill start assist" ( Y page 151).
Maximum gradient-climbing capability
For good road surface conditions, the
maximum gradient-climbing capability is
100%, which corresponds to an approach/
departure angle of 45°. Note that the
vehicle's gradient-climbing capability
depends on the off-road conditions.
Accelerate carefully and make sure that the
wheels do not spin when driving on steep
terrain.
i If 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 recognizes this and brakes the
wheels accordingly. The rear wheel torque
is increased, making it easier to drive off.
i Vehicles with the Enhanced Off-Road
Package have a differential lock for the
transfer case and a differential lock for the
rear axle to improve vehicle traction.
Brow of hill
When driving up an uphill gradient, slightly
reduce pressure on the accelerator
immediately before reaching the brow of the
hill. Use the vehicle's own impetus to drive
over the top of the hill.
This style of driving prevents:
R the vehicle from lifting off the ground on the
brow of a hill
R loss of traction
R the vehicle from traveling too quickly down
the other side
Driving downhill
R Drive slowly.
R Do not drive at an angle down steep
inclines. Steer into the line of fall and drive
with the front wheels aligned straight.
Otherwise, the vehicle could slip sideways,
tip and rollover.
R Before tackling steep downhill gradients,
select shift range 1.
R Activate DSR. If this is not sufficient, brake
gently. When doing so, make sure that the
vehicle is facing in the direction of the line
of fall.
R Check that the brakes are working normally
after a long downhill stretch.
i The special off-road ABS setting enables
a precise, brief and repeated locking of the
front wheels, causing them to dig into the
loose earth. Be aware that the front wheels
easily skid across the ground surface if
completely braked and therefore lose their
ability to steer.
Driving systems
Cruise control
Important safety notes
Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden or towing a trailer, you must
select shift range 1, 2 or 3 in good time. By
doing so, you will make use of the braking
effect of the engine, which relieves the load
on the brake system and prevents the brakes
from overheating and wearing too quickly.
Driving systems179Driving and parkingZ

DISTRONIC
Important safety notes
DISTRONIC regulates the speed and
automatically helps you maintain the
distance to the vehicle detected in front. It
brakes automatically in order to avoid
exceeding the set speed.
On long and steep downhill gradients,
especially if the vehicle is laden or towing a
trailer, you must select shift range 1, 2 or 3
in good time. By doing so, you will make use
of the braking effect of the engine, which
relieves the load on the brake system and
prevents the brakes from overheating and
wearing too quickly.
If a slower-moving vehicle is detected in front,
DISTRONIC causes your vehicle to brake and
maintain the preset distance to the vehicle in
front.
GWARNING
The Distronic requires familiarity with its
operational characteristics. We strongly
recommend that you review the following
information carefully before operating the
system.
GWARNING
When DISTRONIC brakes, the brake pedal is
pulled back (i.e. operated automatically). The
area around the pedal must not be blocked by
obstacles:
R do not place any objects in the footwell.
R ensure that floormats and carpets are fixed
securely. In particular, do not place several
floormats on top of one another.
R do not place your foot under the brake
pedal, as it could become trapped.
Non-compliance could lead you to cause an
accident in which you and/or others could be
seriously injured.
GWARNING
The Distronic is a convenience system. Its
speed adjustment reduction capability is
intended to make cruise control more
effective and usable when traffic speeds vary.
It is not however, intended to, nor does it,
replace the need for extreme care.
The responsibility for the vehicle's speed,
distance to the preceding vehicle and, most
importantly, brake operation to ensure a safe
stopping distance, always remains with the
driver.
The Distronic cannot take street and traffic
conditions into account. Complex driving
situations are not always fully recognized by
the Distronic. This could result in wrong or
missing distance warnings.
If there is no vehicle driving in front of you,
DISTRONIC functions like cruise control at a
speed range between 20 mph (30 km/h) and
120 mph (200 km/h). If a vehicle is driving in
front of you, it functions at a speed range
between 0 mph (0 km/h) and 120 mph
(200 km/h).
Do not use DISTRONIC while driving on roads
with steep gradients.GWARNING
DISTRONIC distance control is not a
substitute for the driver's active involvement.
It does not react to pedestrians or stationary
objects and cannot detect or predict the
road's course and the movements of the
vehicles in front.
DISTRONIC can only brake using 40% of the
vehicle's maximum possible braking force.
The driver must always pay attention to road,
weather and traffic conditions. He must steer,
brake and drive the vehicle so that he
maintains control over it.
High-frequency sources such as toll stations,
velocity measurement systems, etc. may
cause DISTRONIC to malfunction.
GWARNING
The Distronic cannot take road and traffic
conditions into account. Only use the
Distronic if the road, weather and traffic
182Driving systemsDriving and parking

ProblemPossible causes/consequences and M Solutions÷
The yellow ESP ®
warning lamp flashes
while the vehicle is in
motion.At least one wheel is spinning and the electronic traction system
is deactivated to prevent the brakes on the drive wheels from
overheating.XObserve the additional display messages in the multifunction
display.
The electronic traction system switches back on again as soon as
the brakes have cooled down.
The display message disappears and the ÷ warning lamp goes
out.
å
The yellow ESP ®
OFF
warning lamp is lit while
the engine is running.GRisk of accident
ESP ®
and ESP ®
trailer stabilization are deactivated. ESP ®
will not
stabilize the vehicle if it starts to skid or if a wheel starts to spin.
XReactivate ESP ®
.
For exceptions: ( Y page 69).XAdapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
XHave ESP ®
checked at a qualified specialist workshop.֌
The yellow ESP ®
and
ESP ®
OFF warning
lamps are lit while the
engine is running.GRisk of accident
ESP ®
, BAS, PRE-SAFE ®
, hill start assist and ESP ®
trailer
stabilization are not available due to a malfunction. ESP ®
will not
stabilize the vehicle if it starts to skid or if a wheel starts to spin.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.262Warning and indicator lamps in the instrument clusterOn-board computer and displays

when the brakes are applied hard (e.g. when
driving downhill). This would impair braking
efficiency.
You should have the brake fluid renewed at
regular intervals. The brake fluid change
intervals can be found in the Service Booklet.
Only use brake fluid approved by Mercedes-
Benz. Information about approved brake
fluids can be obtained from any authorized
Mercedes-Benz Center.
Coolant
Important safety notes
The coolant is a mixture of water and
antifreeze/corrosion inhibitor. It performs
the following tasks:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
The engine cooling system is filled at the
factory with coolant which contains an
antifreeze/corrosion inhibitor that ensures
protection down to approximately -35 ‡
(-37 † ).
! Only add coolant that has been premixed
with the desired antifreeze protection.
Otherwise, the engine could be damaged.
Further information on coolants and on
filling can be found in the Mercedes-Benz
Specifications for Service Products, MB
Approval 310.1, e.g. on the Internet at
http://bevo.mercedes-benz.com . You can
also consult an authorized Mercedes-Benz
Center.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the cooling system will not be
sufficiently protected from corrosion, and
the boiling point will be too low.
If the coolant has antifreeze protection down
to -35 ‡ (-37 † ), the boiling point of the
coolant in the pressurized system is
approximately 266 ‡ (130 † ).
Your vehicle has a range of aluminum
components. Use of aluminum components
in the engine make it necessary to specifically
match the antifreeze/corrosion inhibitor in
these systems in order to protect the
aluminum parts. Using other antifreeze/
corrosion inhibitors without these
characteristics affects the service life.
The coolant must be used throughout the year
in order to maintain the necessary corrosion
protection and provide protection from
overheating. In the Service Booklet, you can
find information on the intervals for renewal.
The renewal interval is determined by the
coolant type and the engine cooling system
design. The renewal interval in the Service
Booklet is only valid if the coolant is renewed
or replenished with Mercedes-Benz approved
products. Therefore, only use MB 326.0
antifreeze/corrosion inhibitor or another
Mercedes-Benz approved product of the
same specification.
Information on other products with the same
specifications that are approved by
Mercedes-Benz can be obtained at an
authorized Mercedes-Benz Center or on the
Internet at
http://bevo.mercedes-benz.com .
The coolant is checked at every maintenance
interval at an authorized Mercedes-Benz
Center.
The antifreeze/corrosion inhibitor
concentration in the engine cooling system
should:
R be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 † ).
R not exceed 55% (antifreeze protection to
-49 ‡ [-45 † ]); otherwise, heat will not
dissipate as effectively.
If the coolant level is too low, MB 326.0
antifreeze/corrosion inhibitor should be
added. Have the engine cooling system
checked for possible leaks.376Service products and capacitiesTechnical data