TL* THE CONTACT OWNS A 2015 CHEVROLET COLORADO. WHILE DRIVING UPHILL, THE VEHICLE BEGAN TO JERK FORWARD INDEPENDENTLY WITHOUT WARNING. DURING THE FAILURE, THE TRANSMISSION JUMPED IN AND OUT OF GEAR. THE VEHICLE WAS TAKEN TO A DEALER, BUT THE CAUSE OF THE FAILURE COULD NOT BE DETERMINED. THE DEALER STATED THAT THE VEHICLE COULD NOT BE REPAIRED BECAUSE NO FAILURE CODES WERE GENERATED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. CHEVROLET ASSIGNED AN INVESTIGATOR TO DIAGNOSE THE VEHICLE, BUT THE FAILURE COULD BE DUPLICATED. THE CONTACT MENTIONED THAT THE RECURRENCE OF THE FAILURE CAUSED HER EXTREME NECK PAIN. THE FAILURE MILEAGE WAS APPROXIMATELY 28,000. ....UPDATED 06/23/ 17 *BF *AS