my right rear shock on my '95 s500 is squeaking/groaning.i've located it to the bushingthat secures the shock to the sub frame.does anyone out there know how to lubricatethe outside of the bushing or can i swap the rubber bushing at a performance shop.of course my dealer $uggested replacing BOTH shocks for about 2K!i can do alot with the 2K-one of which is put up with the noise!!!