hey, when i drive, and go over little bumps, my rear struts make a clank noise what could this be? the only thing i can think of are the upper strut mounts are worn. but, it only stared doing it after putting on coil overs?

Could be bushings, the struts, or any other part of your suspension. Your new springs are displacing stress onto other components.

It is difficult to track down things such as this as visual inspections will not always reveal problems.

One quick visual check you can do is to look at the rear upper knuckle bushing. These tend to weaken over time and will actually sag toward the front of the car. If they are worn enough, they can hit the upper arm assembly and make a "clanking" noise. Just take a look and see if the upper knuckle is still centered where it meets the arm. If so, move on. If not, search for "rear knuckle bushing" and read up on how to fix it.

ok, i fixed it. it was my upper strut mounts were bad, and they didnt have any bump stops. but it rides good now, thanks guys.