Hey all, new to the site and have questions regarding interchangeable parts. I just purchased a B5100D. Got a good deal because the 4wd didn't work. I should have done some research first and I would have found that Kubota no longer makes the differential or ring gear for this dated tractor. I have searched country wide through a reputable salvage service and have struck out so far. I know through my shop manual and from k-pad parts catalogue that parts on the B5100D, 6100D and 7100D are in common. What I can't find is the the spline, or not sure what the name is, tooth count on the ring gear. I have a donor 6100D that an acquaintance has. Not sure if this would work without more information that I know some fine Kubota expert can give me.