I suppose that this is not as great a problem with M-B's policy of keeping parts available for everything they ever made (if you can afford them), but I just acquired my dream retirement cruiser: an '86 BMW 524TD, and I'm hanging around EBay looking for new parts to build an inventory of the things unique to this model that I might need for the next 20 years or so. I've already acquired a water pump and am considering bidding on a brake master cylinder and some other items which involve combinations of specialized metal and rubber or plastic stuff for which preservation of one without harming the other could be critical. Do any of you have any suggested vapor bag sprays or any mil. spec. treatments which might be available and useful??? Cosmoline is fine for my gun collection, but I don't think it's the answer for some auto parts.