Technical data:fuel requirements, Coolant, Fuel requirements coolants – Mercedes-Benz 2006 C-Class User Manual
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Technical data
Fuels, coolants, lubricants, etc.
In areas where carbon deposits may be 
encountered due to lack of availability of 
gasolines which contain these additives, 
Mercedes-Benz recommends the use of 
additives approved by us for use on 
Mercedes-Benz vehicles. Refer to Factory 
Approved Service Products pamphlet for a 
listing of approved product(s). Follow 
directions on product label. 
Do not blend other fuel additives with fuel. 
This only results 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 listed in the 
Factory Approved Service Products 
pamphlet are not covered by the 
Mercedes-Benz Limited Warranty. 
Fuel requirements
Only use premium unleaded fuel:
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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.
Coolants
The engine coolant is a mixture of water 
and anticorrosion/antifreeze, which 
provides:
ț
Corrosion protection
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Freeze protection
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Boiling protection (by increasing the 
boiling point)
The cooling system was filled at the factory 
with a coolant providing freeze protection 
to approximately -22°F (-30°C) and 
corrosion protection.
If the antifreeze mixture is effective 
to -22°F (-30°C), the boiling point of the 
coolant in the pressurized cooling system 
is reached at approx. 266°F (130°C).