I've been looking into elements for my SD. The stamped part numbers are apparently for the components used to make a pod as 2 very different pods have the same # stamped on the case.

Google search mercedes vacuum element and some pods will come up. Look in the FSM for function & location. Some sites you can get a list of Behr parts that apply to your vehicle.

You could also send Phil an email. The fast way is to order from Phil, pull dash & install. Search & education takes time.

I don't think I'll install a used element as some of my used elements work and some don't. Since the dash is out, I want elements fixed. Dash removal wasn't bad. Only some of the pods can be repaired with new diaphrams but I haven't researched specifics - yet. Again, info on this site and the FSM helps.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.