Stainless and nearly all metals are a predator for Aluminum.
To solve it use always TefGel with SS and Alu.
It is a compound which seals the metals from each other a little bit. [ on Amazon € 50 ]
We used it a lot at sea on the alu-masts and the SS or 8.8 steel mast-fittings and it works well when you check it once a year.
Zinc Galvanized is also a problem. Just a matter of the periodic system.
Only Magnesium is eaten by Aluminum
