So I parked my '90 Wagon w/its '91 auto and rear 3.9 VLSD into the side of one, and 'stuck' it there.....
(BTW, I have the 4WD Diff Lock Mod installed and it was in use.)
....I wanted to see if 3 wheels were spinning. But I only had one @ the front and one in the rear.

I'm confused because I expected to see both rears turning.
The back end kicks out if I punch it in slippery conditions....isn't that a 'sign' of an LSD? And I don't recall that happening on my other Legacy AWDs???
Even had a little excitement on snow/ice covered Snoqualmie Pass when it downshifted to 2nd to pass a few cars and the rear end went sideways @ 40.

I got the VLSD used w/unknown mileage. Do they wear out? And if so, are they serviceable? If I jack up the rear end and both wheels spin in the same direction a valid test for a VLSD?
It does have the 'sticker' labeling it as a 3.9 VLSD, too.
Thanks as always!