Some 2007-08 Jeep Wranglers, 2008 Dodge Durangos and 2008 Jeep Grand Cherokees and Commandeers with 3.8-liter engines may turn on the oil change monitor on the instrument cluster prematurely.
According to Chrysler, the condition occurs on trucks built before Feb. 22, 2008, is usually intermittent, and frequently occurs after the battery is disconnected or the monitor has been reset following an oil change. Software gremlins in the PCM are the likely cause of the trouble. Reprogramming the module with an updated calibration is the only surefire fix. Check with a dealer for the specifics of the flash.