Premium-Grade Unleaded Gasoline; Additives - Mercedes-Benz 2011 G-Class Operator's Manual

Service products and capacities
278
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging to your
health.

Premium-grade unleaded gasoline

! To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline must be used.
If premium-grade unleaded gasoline is
unavailable and regular gasoline is used,
observe the following precautions:
only fill the fuel tank to half full with
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regular unleaded gasoline and add the
rest as soon as possible with premium-
grade unleaded gasoline.
do not drive at the maximum speed.
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avoid sudden acceleration.
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when the vehicle is carrying a light cargo,
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e.g. two passengers without luggage, do
not allow the engine to rev above
3000 rpm.
when the vehicle is fully loaded or being
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operated in mountainous terrain, do not
depress the accelerator pedal further
2
than / of the pedal travel.
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Fuel requirements
Use only premium-grade unleaded gasoline.
The octane number should be at least 91.
Details can be found on the gas pump. The
octane number is the average value of the
Research Octane Number (RON) and the
Motor Octane Number (MON): (RON +
MON) / 2, also known as knock resistance.
Reformulated Gasoline (RFG) and/or
unleaded gasoline with additives can be used
if the concentration of the additives in the fuel
does not exceed 10%, e.g.:
Ethanol
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TAME
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ETBE
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IPA
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TBA
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For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline
including other additives must not exceed
3 %.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline, can be used.
All of these mix fuels must fulfill the fuel
requirements, e.g.:
knock resistance
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boiling point
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vapor pressure
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Additives in gasoline
One of the major problems in engine design
is the creation of carbon deposits during the
process of burning fuel. Mercedes-Benz
recommends that you use fuel brands that
have the additives which prevent the build up
of carbon deposits.
If you use fuels without these additives for a
longer period of time, there may be a build up
of carbon deposits, especially on the inlet
valves and in the combustion chamber.
This could lead to engine running problems,
e.g.:
longer engine warm-up phase
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uneven idle
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engine noise
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misfiring
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loss of power
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In areas where carbon deposits can build up
due to the lack of availability of gasoline with
the corresponding additives, Mercedes-Benz
recommends the use of additives that have
been approved for Mercedes-Benz vehicles.
Consult an authorized Mercedes-Benz Center
or visit http://www.mbusa.com (USA only)
to view a list of approved products. Observe
the instructions for use in the product
description.