Mercedes-Benz ML320. Manual — part 119

303

Technical data

Fuels, coolants, lubricants etc.

Premium unleaded gasoline

Fuel requirements

Use only premium unleaded meeting
ASTM standard D 439:

앫

The octane number (posted at the
pump) must be 91 min. It is an average
of both the Research (R) octane num-
ber and the Motor (M) octane number:
(R+M)/2). This is also known as the
ANTI-KNOCK INDEX.

Unleaded gasoline containing oxygenates
such as ethanol, IPA, IBA and TBA can be
used provided the ratio of any one of these
oxygenates to gasoline does not exceed
10%; MTBE must not exceed 15%.

The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.

Using mixtures of ethanol and methanol is
not allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.

These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc.

Gasoline additives

A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build-up of carbon depos-
its.

After an extended period of using fuels
without such additives, carbon deposits
can build up especially on the intake valves
and in the combustion area, leading to en-
gine performance problems such as:

앫

Warm-up hesitation

앫

Unstable idle

앫

Knocking/pinging

앫

Misfire

앫

Power loss

Do not blend other specific fuel additives
with fuel. This only results in unnecessary
costs and may be harmful to the engine
operation.

!

To maintain the engine’s durability and
performance, premium unleaded gaso-
line must be used. If premium unleaded
is not available and low octane fuel is
used, follow these precautions:

앫

Have the fuel tank only partially
filled with unleaded regular and fill
up with premium unleaded as soon
as possible.

앫

Avoid full throttle driving and abrupt
acceleration.

앫

Do not exceed an engine speed of
3000 rpm if the vehicle is loaded
with a light load such as two per-
sons and no luggage.

앫

Do not exceed

2

/

3

of maximum ac-

celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.

304

Technical data

Fuels, coolants, lubricants etc.

Damage or malfunctions resulting from
poor fuel quality or from blending specific
fuel additives are not covered by the
Mercedes-Benz Limited Warranty.

Coolants

The engine coolant is a mixture of water
and anticorrosion / antifreeze, which pro-
vides:

앫

Corrosion protection

앫

Freeze protection

앫

Boiling protection (by increasing the
boiling point)

The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -35°F (-37°C) and corro-
sion protection.

If the antifreeze mixture is effective to
-22°F (-30°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).

The coolant solution must be used year
round to provide the necessary corrosion
protection and increase in boil-over pro-
tection. Refer to Service Booklet for
replacement interval.

To provide important corrosion protection,
the solution must be at least 45%
anticorrosion/antifreeze (equivalent to
freeze protection to approx. - 22°F
[-30°C]). If you use a solution that is more
than 55% anticorrosion/antifreeze (freeze
protection to approx. - 49°F [-45°C]), the
engine temperature will increase due to
the lower heat transfer capability of the so-
lution. Therefore, do not use more than
this amount of anticorrosion/antifreeze.

If the coolant level is low, water and MB
anticorrosion/antifreeze should be used
to bring it up to the proper level (have cool-
ing system checked for signs of leakage).
Please make sure the mixture is in accor-
dance with label instructions.

The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, con-
sult your authorized Mercedes-Benz Light
Truck Center.

305

Technical data

Fuels, coolants, lubricants etc.

Anticorrosion/ antifreeze

Your vehicle contains a number of alumi-
num parts. The use of aluminum compo-
nents in motor vehicle engines
necessitates that
anticorrosion/antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. (Failure to use
such anticorrosion/antifreeze coolant will
result in a significantly shortened service
life.)

Therefore, the following product is strongly
recommended for use in your vehicle:
Mercedes-Benz Anticorrosion/Antifreeze
agent.

Before the start of the winter season (or
once a year in hot southern regions), you
should have the anticorrosion/antifreeze
concentration checked. The coolant is also
regularly checked each time you bring your
vehicle to your authorized Mercedes-Benz
Light Truck Center for service.

306

Technical data

Fuels, coolants, lubricants etc.

Anticorrosion/antifreeze quantity

Model

Approx. freeze protection

– 35°F (– 37°C)

– 49°F (– 45°C)

ML 350, ML 500,

6.4 US qt (6.0 l)

7.0 US qt (6.6 l)