RE: Allison Transmission Questions Hey AllisonMan, I have a 04 Southwind on a workhorse chasis and a 5 speed allison transmission. I took it to a local shop recently concerned about whinning noise. They said everything checked out. Of course they couldn't get the tranny to whine. What it does, intermittently, is shift normal but the tranny will keep a high pitch whine for 30 seconds to a minute or more then it goes away. Is that anything to be worried about? This happens most of the time from 4th to 5th gear and usually on a down shift to get over a hill.