7
Service Products
Fuel Requirements
Gasoline Engines
Reformulated gasolines (RFG) and/or
unleaded gasoline containing oxygenates
such as Ethanol, TAME, ETBE, IPA, IBA, and
TBA can be used provided that the ratio of
any one of these oxygenates to gasoline
does not exceed 10%. MTBE may be added
up to 15%. The ratio of Methanol to
gasoline must not exceed 3% plus co-
solvents.
Mixtures of Ethanol and Methanol must
not be used. Gasohol, which contains 10%
Ethanol and 90% unleaded gasoline, can
also be used. These blends must also meet
all other fuel requirements such as
resistance to spark knock, boiling range,
vapor pressure, etc.
Gasoline Additives
Of major concern among various engine
manufacturers is the carbon build-up
caused by gasoline. MERCEDES-BENZ
recommends using only quality gasoline
containing additives that prevent the build-
up of carbon deposits.
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 engine performance problems such as:
• warm up hesitation,
• unstable idle,
• knocking /pinging,
• misfire, and
• power loss.
In areas where carbon deposits may be
encountered because gasoline with
additives are not available, Mercedes-Benz
recommends the use of additives
approved by us for use on Mercedes-Benz
vehicles (
page 15).
DO NOT blend other fuel additives with the
fuel. These additional additives only result
in unnecessary cost and may be harmful to
engine operation.
Damage or malfunction resulting from poor
fuel quality or from blending additional fuel
additives other than those tested and
approved by us for use on Mercedes-Benz
vehicles (
page 15) are not covered by
the Mercedes-Benz Limited Warranty or by
any pre-owned or Extended Limited
warranties.
Premium Unleaded
Use only premium unleaded gasoline
meeting ASTM standard D439. The octane
number posted at the pump must be at least
91 min. In the U.S., this octane number is an
average of the Research octane number (R)
and the Motor octane number (M): (R + M) /
2. The octane number is also known as the
Anti-Knock Index.