17" hmm.. if your riding stock height, you should not have this problem.. Inless your shocks are shot to hell. If there is already a drop How low is it ?.. Coil overs COULD help, But make sure your shocks are good, other wise, you will just end up with crappy ride quality with new coil overs, and that isnt cool.

But its JUST the right rear ??.. so Id say check your shocks out.