Jeep 2005 Liberty - Manual (Page 276)

The suggested rotation method is the “forward-cross”
shown in the following diagram. FUEL REQUIREMENTS (GASOLINE ENGINES)
Your engine is designed to meet all emis-
sions regulations and provide excellent
fuel economy and performance when us-
ing high quality unleaded gasoline having
an octane rating of 87. The use of premium
gasoline is not recommended. The use of
premium gasoline will provide no benefit over high
quality regular gasoline, and in some circumstances may
result in poorer performance.
Mid-grade gasoline (89 octane) will enhance engine per-
formance during the following conditions (3.7L Only):
• Hot weather
• Towing
• Hard accelerations
• Hilly terrain
• Low humidity
276 STARTING AND OPERATING