There is no reason that would damage your transmission at all. It dosent care if you have a load on it or not. And that short a time it wouldn't even matter if you had no fluid in it. Its all good!

hes right you know, i recently help a friend with a turbo, and when he started the car jacked up in the front the drivers side wheel would spin, all on its own,
i dont know the physics behind it, but nothing to fear.

Nope, it's all good. This is normal for cars with manual transmissions. The wheels are spinning because with the input shaft of the tranny spinning the fluid moving around in the tranny causes the output shafts to spin.

There isn't much force behind the movement, in fact you could easily hold the wheel while in neutral and stop the rotation.

Out of curisoty, when jacked up all 4 should all four spin in neutral? (Mine doesnt but I'm curious) and I'm guessing if in first all 4 should spin equally?

Nah you'r fine, It would only get damaged if you drove arround like that, Ask me how i know haha.
Since it was just a few seconds i doubt something happened.

Thanks everybody! @ urbansmoker, if all 4 are moving, I believe that would be a clutch dragging issue.. mine doesn't spin all 4 while jacked up

Urban, I would think the additional friction from all the extra stuff for the rears would overpower the small amount of friction from the fluid...

therefore, no, all 4 most likely won't spin unless its cold as crap outside.

hey urban, mines dont spin at all. " just saying."

I havnt tried yet was just curious cause I'll probably check for drag which i havnt had an issue so far just pickin my brain