The picture below is a Detroit Locker. The large REM polished 85# spring in the foreground was removed by me and the barely visible orange 58# spring in the small hole in the differential in the background was put in by me. The lighter the spring the easier the Detroit Locker releases. They still pop and crack when they release, just not quite as loud with a lighter spring. I have disassembled and reassembled several and they do in fact look like the 'exploded' diagram in an earlier post. Although not a 'full spool' these are the most bullet proof 'limited slip' made, not even a close second. Most people don't need them and most can't tolerate to violence required to unlock them during normal driving.
Oh, as a side note, helical gear can and do whine. It is typically a backlash issue. If you notice in the 'exploded' diagram of the TruTrac in an earlier post, there is a lack of any kind of bearing that would support any of those gears. So they are constantly forced out against the case in every direction. Brilliant design, but lots of them whine. Especially after many miles once the case has worn. Really they are similar to an Auburn in that respect. Planetary gears in automatic transmissions whine when backlash isn't controlled. I have 'quieted down' several TH400s by tighten up the planetaries with shims. Straight cut gears are worse, but helical gears still whine. Show me a BW or Muncie that didn't. The straighter the cut, the stronger and louder the gear. The more angle, the weaker and quieter...………..typically.
Back to the original subject, a TruTrac is a good differential. My exhaust is probably just too quiet.
