Was checking under my seat for something today and found both the right hand seat bolts missing and both left hand ones very loose. Its a 2004 with 240 hours and I guess its one of those things that just comes loose with all the bouncing around i do. Easy fix with some 10mm bolts but If it happened to me you should take a look at yours. Better in the garage than at a 30 degree side slope. I added some thick lockwashers for that extra measure.