Thank you for letting me join and thank you to everyone for experience and insight. I don't have the 850 at the moment or parts book. Did JD use the same planet pinion housing and gear on the 850 as they did on the 750?
Welcome to HEF Skidsteer79 . Link to Deere's online parts catalog https://partscatalog.deere.com/jdrc/
Thanks Diesel Dave