Fuel Requirements; L Engine; Reformulated Gasoline - Jeep GRAND CHEROKEE 2021 Owner's Manual

386 TECHNICAL SPECIFICATIONS
NOTE:
If in doubt about the correct tightness, have
them checked with a torque wrench by an
authorized dealer or service station.
After 25 miles (40 km), check the lug nut/bolt
torque to be sure that all the lug nuts/bolts are
properly tightened.
Torque Patterns
WARNING!
To avoid the risk of forcing the vehicle off the
jack, do not tighten the lug nuts/bolts fully
until the vehicle has been lowered. Failure to
follow this warning may result in personal
injury.

FUEL REQUIREMENTS

While operating on gasoline with the required
octane number, 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 a dealer immediately. Use
of gasoline with a lower than recommended
octane number can cause engine failure and
may void 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 considering service for the
vehicle.
3.6L E
NGINE
Do not use E-85 flex fuel or ethanol blends
greater than 15% in this engine.
This engine is designed to meet all
emissions regulations and provide
optimum fuel economy and
performance when using high quality
unleaded "Regular" gasoline having a posted
octane number of 87 as specified by the
(R+M)/2 method. The use of higher octane
"Premium" gasoline is not required, as it will
not provide any benefit over "Regular"
gasoline in these engines.
5.7L E
NGINE
Do not use E-85 flex fuel or ethanol blends
greater than 15% in this engine.
This engine is designed to meet all
emissions regulations and provide
satisfactory fuel economy and
performance when using high-quality
unleaded gasoline having an octane 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.
R G
EFORMULATED ASOLINE
Many areas of the country require the use of
cleaner burning gasoline referred to as
"Reformulated Gasoline". Reformulated
gasoline contains oxygenates and are
specifically blended to reduce vehicle
emissions and improve air quality.
The use of reformulated gasoline is
recommended. Properly blended reformulated
gasoline will provide improved performance
and durability of engine and fuel system
components.