2008 Mercedes C-Class Owner's Manual - Page 483

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 (USA only), or contact an authorized Mercedes-Benz Center 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 the engine operation. Fuel requirements Only use premium unleaded fuel: The octane number (posted at the pump) must be 91 min. It is an average of both the Research Octane Number (RON) and the Motor Octane Number (MON): (RON+MON)/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 co-solvents. 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. Flexible Fuel Vehicles (USA only) C 300 and C 300 Sport (with automatic transmission*) are Flexible Fuel Vehicles. Flexible Fuel Vehicles are identified by a label reading Premium gasoline or E85 only! on fuel filler flap). These vehicles are designed to operate on premium unleaded gasoline or Ethanol fuel (E85), or on any mixture of these two. Ethanol fuel (E85) is a mixture of approximately 85% Ethanol and 15% unleaded gasoline. Warning! ! 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 are not covered by the Mercedes-Benz Limited Warranty. For a listing of approved products, refer to the Factory Approved Service Products pamphlet (USA only) or contact an authorized Mercedes-Benz Center. G Ethanol fuel (E85) and its fumes are highly flammable, poisonous and burn easily. Ethanol fuel can cause serious injuries if ignited or if you come into contact with it or inhale fumes of it. Avoid inhalation of Ethanol fumes and skin contact with Ethanol. Extinguish all open flames before fueling. Never smoke or create sparks close to Ethanol. 482