Front passenger seats loosened at the floor level (perhaps from their anchorage to the floor or at their tracks). specifically, rear part of seats can move up and down and forward on an arc with driver and passenger in respective seats. event happens when decelerating and when vehicle is diving forward as a result of a bump. this unintended seat movement causes the driver to move closer to the steering wheel and windshield with the seat. the front passenger also gets pushed forward toward the windshield and dash. this issue happen(s/ed) at city and highway speeds. issues were made aware to service technicians at 3748mi on 08 oct. 16 and 4573mi on 22 oct. 16. driver's seat is loosening again with vehicle at 9090mi on 03 mar. 17.