Hey Tom, thanks so much for doing that, and thanks to all who have contributed ideas and tests. My test results are certainly a bit different from others. Just now I again tried stopping one rear while all 4 are spinning at idle. Generally I get the ABD going off and there is a kick and it starts spinning again. I have gloves on and am holding it strongly enough to slow the idle speed. Certainly it is not slipping too badly then! But at one point the ABD was off (the red abd warning light was on) and I could hold one rear fixed with little force while the other was spinning and it didn't load the engine. Not good. Can you have an intermittent LSD?.

So I think I will do is look up what is required to build the tool required to torque test it with the axles removed.

To think this all started with the notion it would be good to change the fluid!