Tim is correct. Open driveline, with the original housing and a pumpkin installed from a 59. Tim, mid last year, I changed the 3.90 to a 3.38 ring and pinion from Yukon. It has a dang whine in it about 45mph. Yukon sent me another new one but it was worse than the first. I gave up and put the first 3.38 back in it.
I just don't drive 45 and I'm ok
