Never had a problem with same. Recently, I can't recall where, I read a post on a forum where the after run oil they used was "Marvel Mystery Oil" air tool specification. I run a CNC mill and use die grinders all day and also use "air-tool" oil in areas of my machine, not Marvel however.
Was this individual just referring to good old fashioned "Marvel Mystery Oil", as air tool oil, or do they make that as well?
Thanks,
Bob