I recently changed rear diff oil on my 06 Ram 1500.
Heres the thing, I put in the valveline 75w-140 full synthetic labeled “limited slip” should I assume this stuff has the friction modifiers already in it? It doesn’t say on bottle. Thanks

 

That's what the 'limited slip' is all about. It *should* have the additive in it. If the rear chatters around corners though, wouldn't hurt to add a bit more.

 

Ditto. It already has the additive. Adding more will actually cause too much 'bite' and prematurely wear out the diff