I'm amazed you've gotten that many miles on those A arms. If they squeak or have any rust near the rubber or the rubber is torn, replace them immediately. Your inner tire wear is probably another indicator and alignment difficulties is another.

I had one outer ball joint snap. Fortunately, it was in a parking lot while making a lock turn. Car came down with fender lip onto tire. Due to MB's structural integrity, the fender didn't bend. Flat bed operator had to use a jack as a dolly for the broken wheel. Interesting to watch.

Febi Bilstein Mahle still made in Germany. Beware if cheep made in China.