QUOTE(Evil914 @ Apr 13 2016, 12:38 AM)
At the risk of sounding stupid, how would one tell?
Turn one of the output flanges. If the other side turns in the same direction it is a LSD. If it the other side turns the other way then it is a open diff. Plus you should find a small aluminum tag on the “SD Oil Shell 1747A”. Lastly the part number along the bottom rib should be 914/11/10 HB xxxxxxx The HB means factory LSD.
Hope this helps.