2006 Jeep Wrangler Owner's Manual - Page 272

272 MAINTAINING YOUR VEHICLE The best time to check the engine oil level is about 5 minutes after a fully warmed engine is shut off, or before starting the engine after it has sat overnight. Checking the oil while the vehicle is on level ground will improve the accuracy of the oil level readings. Maintain the oil level between the ADD and SAFE markings on the dipstick. Adding 1 U.S. Quart (0.95L) of oil when the reading is at the ADD mark will result in a SAFE reading on these engines. CAUTION! Overfilling or underfilling the crankcase will cause aeration or loss of oil pressure. This could damage your engine. Change Engine Oil Road conditions as well as your kind of driving affect the interval at which your oil should be changed. Check the following to determine if any apply to you: • Day or night temperatures are below 32°F (0°C) • Stop and go driving • Extensive engine idling • Driving in dusty conditions • Short trip driving of less than 10 miles (16.2 km)