Jeep 2015 Grand Cherokee SRT - Owner Manual - Manual (Page 474)

The TPM sensors are regulated under one of the follow-
ing licenses:
United States MRXMERCTX1
Canada 2546A-MERCTX1
FUEL REQUIREMENTS
6.4L Engine
The 6.4L engine is designed to meet all emis-
sions regulations and provide excellent fuel
economy and performance when using high-
quality premium unleaded gasoline with an
octane rating of 91 or higher.
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 experi-
ence these symptoms, try another brand of gasoline
before considering service for the vehicle.
Over 40 auto manufacturers worldwide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) which define fuel properties
necessary to deliver enhanced emissions, performance,
and durability for your vehicle. The manufacturer recom-
mends the use of gasolines that meet the WWFC speci-
fications if they are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline.”
Reformulated gasoline contain oxygenates and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
472 STARTING AND OPERATING