Reformulated Gasoline; Gasoline/Oxygenate Blends - Chrysler 2007 Aspen Owner's Manual

312 STARTING AND OPERATING
gasoline will provide no benefit over high quality regular
and mid-grade gasolines, and in some circumstances
may result in poorer performance.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of "regular" gasoline be-
fore considering service for the vehicle.
Over 40 auto manufacturers world-wide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance
and durability for your vehicle. We recommend the use
of gasolines that meet the WWFC specifications if they
are available.

Reformulated Gasoline

Many areas of the country require the use of cleaner
burning gasoline referred to as "Reformulated Gasoline."
Reformulated gasolines contain oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
We strongly support the use of reformulated gasolines.
Properly blended reformulated gasolines will provide
excellent performance and durability for the engine and
fuel system components.

Gasoline/Oxygenate Blends

Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE and ETBE. Oxygen-
ates are required in some areas of the country during the
winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.