Jeep Grand Cherokee 2011 Owner's Manual page 492

490 MAINTAINING YOUR VEHICLE
Change Engine Oil
The oil change indicator system will remind you that it is
time to take your vehicle in for scheduled maintenance.
Refer to "Maintenance Schedule" for further information.
NOTE: Under no circumstances should oil change
intervals exceed 8,000 miles (13 000 km) or six months,
whichever occurs first.
Engine Oil Selection
For best performance and maximum protection for all
engines under all types of operating conditions, the
manufacturer recommends engine oils that are API Cer-
tified and meet the requirements of Chrysler Material
Standard MS-6395.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API Certified engine oils.
CAUTION!
Do not use chemical flushes in your engine oil as the
chemicals can damage your engine. Such damage is
not covered by the New Vehicle Limited Warranty.