Electronic Stability Control (ESC) effect on SUV Rollover and Handling Stability was evaluated using a first generation ESC equipped 2004 Mercury Mountaineer. Fishhook and Sine with Dwell tests were conducted with the ESC turned off and the ESC turned on. Even with ESC turned on the 2004 Mercury Mountaineer tipped up in Fishhook testing and responded with spinout in the Sine with Dwell testing. Follow-up comparison testing with the Ford corporate twin, 2005 Ford Explorer equipped with second generation ESC (Roll Stability Control, RSC), demonstrated successful completion of both test including tests with maximum roof load and load that caused a maximum rear weight bias (at the GRAWR).