Best solution is to get a new actuator. Good enough solution is to get replacement diaphragms. Replacement diaphragms are only so good in dual chamber applications.
I don't think FastLane and PartsShop offer diaphragms so try George Murphy or a place called
www.autolux.com or something like that. It's in the archives.
Sixto
95 S420
91 300SE
87 300SDL
83 300SD