240 DRIVING AND OPERATINGFuelGM recommends the use of TOP TIERDetergent Gasoline to keep the enginecleaner and reduce engine deposits.See www.toptiergas.com for a list ofTOP TIER Detergent Gasolinemarketers and applicable countries.Do not use any fuel labeled E85 orFlexFuel. Do not use gasoline withethanol levels greater than 15% byvolume.For the 2.0L L4 turbo engine (LTG),premium unleaded gasoline meetingASTM specification D4814 with aposted octane rating of 93 is highlyrecommended for best performanceand fuel economy. Unleaded gasolinewith an octane rated as low as 87 canbe used. Using unleaded gasolinerated below 93 octane, however, willlead to reduced acceleration and fueleconomy. If knocking occurs, use agasoline rated at 93 octane as soon aspossible, otherwise, the engine couldbe damaged. If heavy knocking isheard when using gasoline with a93 octane rating, the engine needsservice.For the 3.6L V6 engine (LGX), useregular unleaded gasoline meetingASTM specification D4814 with aposted octane rating of 87 or higher.Do not use gasoline with a postedoctane rating of less than 87, as thismay cause engine knock and willlower fuel economy.For the 3.6L twin turbo V6 engine(LF4), use premium unleaded gasolinemeeting ASTM specification D4814with a posted octane rating of 93.If unavailable, unleaded gasoline witha posted octane rating of 91 may beused, but with reduced performanceand fuel economy. If the octane is lessthan 91, the engine could be damagedand the repairs would not be coveredby the vehicle warranty. If heavyknocking is heard when using gasolinerated at 93 octane, the engine needsservice.Prohibited FuelsCautionDo not use fuels with any of thefollowing conditions; doing so maydamage the vehicle and void itswarranty:. For vehicles which are notFlexFuel, fuel labeled greaterthan 15% ethanol by volume,such as mid-level ethanolblends (16 – 50% ethanol),E85, or FlexFuel.. Fuel with any amount ofmethanol, methylal, andaniline. These fuels cancorrode metal fuel systemparts or damage plastic andrubber parts.. Fuel containing metals suchas methylcyclopentadienylmanganese tricarbonyl(Continued)
