2009 Chrysler Aspen Owner Manual - Page 340

338 STARTING AND OPERATING MMT In Gasoline MMT is a manganese containing metallic additive that is blended into some gasoline to increase octane. Gasoline blended with MMT provides no performance advantage beyond gasoline of the same octane number without MMT. Gasoline blended with MMT reduces spark plug life and reduces emission system performance in some vehicles. The manufacturer recommends that gasoline without MMT be used in your vehicle. The MMT content of gasoline may not be indicated on the gasoline pump, therefore, you should ask your gasoline retailer whether or not his/her gasoline contains MMT. It is even more important to look for gasolines without MMT in Canada, because MMT can be used at levels higher than those allowed in the United States. MMT is prohibited in Federal and California reformulated gasoline. Materials Added To Fuel All gasolines sold in the United States are required to contain effective detergent additives. Use of additional detergents or other additives is not needed under normal conditions and would result in unnecessary cost. Therefore, you should not have to add anything to the fuel. Fuel System Cautions CAUTION! Follow these guidelines to maintain your vehicle's performance: • The use of leaded gas is prohibited by Federal law. Using leaded gasoline can impair engine performance, damage the emission control system. (Continued)