According to 2008 Jeep Liberty Owner’s Manual, SAE 5W-20 engine oil is recommended for all operating temperatures.
This engine oil improves low temperature starting and vehicle fuel economy. The engine oil filler cap also shows the recommended engine oil viscosity for your engine.
For best performance and maximum protection under all types of operating conditions, the manufacturer recommends engine oils that are API Certified and meet the requirements of DaimlerChrysler Material Standard MS-6395.
This symbol means that the oil has been certified by the American Petroleum Institute (API). The manufacturer only recommends API Certified engine oils.
One of the cornerstones of do-it-yourself car maintenance jobs is the home oil change. It's a simple process that requires few tools, and it's a sure way to save some money while you avoid the hassle of sitting in a dull waiting room somewhere reading outdated magazines.
More than anything, the basic oil change is a great way to connect with your vehicle and take some control over its maintenance. The time you spend under the hood and under the car affords you an excellent opportunity to look around and see if anything else needs attention. Learn how to change your oil at Edmunds.com.