ATF in rear diff????

[TFB]

I've pick up a spare front and rear diff from ebay so I can keep the truck on the road while I fiddle about with ratios and lockers.

I drained out the new front diff and got the usual foul smelling gear box oil, but when I drained out the new rear it looks like (and smells like) thick ATF fluid. I don't think it's a LSD as it doesn't act like one when the input shaft is turned (and the code on the breaker truck was wrong).

Any ideas if ATF is used in rear diff's or why????

Regards

TFB

[Albannach]

ATF isn't used in rear diffs..