Most likely, the Nitrogen accumulators need replacement. As for wear items, I would replace the bushings on top of the strut towers and the spring shims. If the sagging is different from side-to-side, I would inspect the leveling valve and the springs. Finally, if there is general slop in the rear, the subframe mount bushings could be replaced. Hope this helps, Andrew Seidel.
85 500SEC Lorinser
83 300D Turbo