See also:

Engine Oil Selection
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 Chrysler Material ...

Going & Stopping
The Liberty may have gotten all-new sheet metal and a different interior, but its engine is exactly the same. The 210-horsepower V-6 is completely adequate, especially at highway cruising speeds. ...

Extreme Cold Weather (Below –20°F Or 29°C)
To ensure reliable starting at these temperatures, use of an externally powered electric engine block heater (available from your authorized dealer) is recommended. ...