Tl*the contact rented a 2011 lincoln navigator. the contact stated that while driving approximately 50 mph, the vehicle suddenly accelerated to 70 mph and when the contact attempted to slow down, it did not respond. the vehicle was able to stop by placing it in low gear and removing the key from the ignition. the vehicle was towed to a dealer but they were unable to give him any details as it was a rental vehicle. the repairs were unknown. the failure mileage was approximately 300. updated 2/17/11 *cn updated 04/27/11