Rear Diff Oil and LSD Additive

[Mile High VX]

I'm not too sure about just what the LSD additive is or what it does (Google didn't help). Hopefully a gear head will chime in & shed some light on the subject.

From a product website:

Limited Slip Additive

If you get a "chatter" from the rear axle when starting from a stop, and turning at the same time, you need to add this additive to your rear end oil. This is due to the clutches in the diff. locking and un-locking. The Limited Slip Additive assists with the applying and releasing of the clutch plates. One container/part number needed per rear end oil change.