6.4L Engine
This engines is designed to meet all
emissions regulations and provide sat-
isfactory fuel economy and perfor-
mance when using high quality un-
leaded gasoline having a posted
octane number range of 87 to 89 as
specified by the (R+M)/2 method. The
use of 89 octane “Plus” gasoline is recommended for
optimum performance and fuel economy.
While operating on gasoline with an octane number of
87, hearing a light knocking sound from the engine is not
a cause for concern. However, if the engine is heard
making a heavy knocking sound, see your dealer imme-
diately. Use of gasoline with an octane number lower
than 87 can cause engine failure and may void or not be
covered by the New Vehicle Limited Warranty.
Poor quality gasoline can cause problems such as hard
starting, stalling, and hesitations. If you experience these
symptoms, try another brand of gasoline before consid-
ering service for the vehicle.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline”.
Reformulated gasoline contains oxygenates and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The use of reformulated gasoline is recommended. Prop-
erly blended reformulated gasoline will provide im-
proved performance and durability of engine and fuel
system components.
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STARTING AND OPERATING