It has been max 90 thousandths over for as long as I can remember (back to 1967 at least). Having said that, drums are darn cheap for bendix brakes on light trucks, like $40. At summit racing for ACDelco’s.
In working with my local machinist on converting my 46 1/2 ton to front bendix (long story, truck came to me with bendix rears, huck fronts), plan is to secure our brand new drums to the hubs and turn them just enough to be sure they are centric to the axels.
Chuck
