infamous 4 speed whine?

The loud whine heard in reverse is because reverse in any manual trans that I have ever seen uses straight cut gears, as does bull low in most truck transmissions, and pre synchro car transmissions. Straight cut gears are stronger, but noisy. The infamous Muncie rock crusher transmission was noisy in forward gears because it used gears that were cut near straight, for strength. Helical gears are quiet, but are much harder to shift or engag while rotating (straight cut gears can be by double clutching), thus helical cut gears use synchros.