Chris and Ed, I don't think it does, but in low range of the over-under you are running the lube circuits and no pressure to either clutch circuit. In the transmission if you ran the over under in overdrive and the transmission in high range if you ever did the math you would not believe how fast that low range gear is spinning!. And it needs oil to keep it lubed! In low range both ways, it is plus as far as gear speeds go. We talked about that one time my friendly service rep(who is no longer with us) and I. The topic was talked about it in service school, but that was probably before you were born Chris. Ed, are you working the tractor on level ground when you are using the PTO? I remember one case on a 50 series over in PA the man did not keep the oil level to the other plug and he was complaing about a transmission problem That topic was covered in the operators manual.