The bell housing bolts are staying tight, so I guess that problem is solved. The leaking oil was coming out the breather on the transfer case. The rear end was full of oil. No hydraulic oil leaking when the tractor isn't being run, so I assume that the pan between the hydraulic oil and the tranny is okay. PTO isn't working properly so am suspecting a leak into the rear end from the PTO. we'll see. Anybody got any ideas?