rear suspension question

when im on the interstate (or going atleast 50 or 60 on road) and I hit a decent bump, if no one is in the back seat, the rear end comes off the ground for a sec after hitting the bump, basically like hitting a ramp, it actually gets a small amount of air (quite an experience on a sharp turn) and if some1 is in the back seat, something bottoms out (makes that sound anyways, a loud thump) in the rearend area, im guessing the struts. Unless its something on the frame or something actually hitting the road, im not sure. Either way, is this because my rear struts are wearing out, or is this something else all together? Its on a 95 gt, stock suspension, which to my knowledge, hasnt been changed, and it has 145000 miles on it. any help is appreciated.

p.s. the rear end may not come completely off the ground, but it does enough so that my tires start spinning and my rear ends wants to come around if im on a sharp turn.

Sounds more like your springs are worn out then your struts. Your struts could be worn out too with 145,000 miles on them, but what your describing, sounds more like worn spings to me. If you said your cars seems to bounce alot, then I'd say struts, because the struts dampen the bouncey effect that the spings give.

thx man, the car doesnt bonce much, my dad's old car use to bounce when you hit a bump, so i know what your talking about. so just replace it all and get some camber plates, lower it while im at it, and all should be good then?