"Limited Slip and positraction (posi) differentials are designed to "limit" the tendency of open differential to send power to a wheel that lacks traction and redirect the power to a degree to the other wheel of the axle. The Limited Slip and Positraction differential will send power to both wheels equally when traveling straight, however when one wheel spins due to a lack of traction, the differential will automatically provide torque to the other wheel with traction. Limited Slip and Positraction (posi) differentials limit the loss of torque to a slipping wheel through various mechanisms such as clutches, gears cones, and other methods dependant on the unit. ((((--->The limited slip and positraction will not provide 100% lock up of the differential in extreme situations such as when a wheel completely looses traction. <----)))) Limited Slip and Positraction (posi) differentials are recommended for daily driven vehicles and are used in many applications where traction is sometimes needed as in emergency vehicles. They are also ideal for front axles of 4x4 vehicles that are not equipped with front hubs that can be disengaged. The term "positraction" ("posi" for short) was used by General Motors years ago for their limited slip differential and has been used to refer to limited slips since."

Thats the explanation offroad.com gives on the lsd so just because only one tire spins sometimes has nothing to do with whether or not the lsd is functioning properly or not. I have an aubrun lsd now and in the picture below because of my flexing only the left wheel was spinning because it was almost floating the other tire was gettin no power whatsoever.

 

So if i put in Royal Purple gear lube, I dont have to add a friction modifier since it's already in there right? Or do i still need to add some?

 

If it states that it is already in there, then, no, you do not need to add any more.

 

RP comes with the friction modifier already added, so you're good to go

 

In the 11.5" AAM axle they use a gear-driven locker; there are no clutches and no need for an additive to the gear lube. I thought the smaller AAM rear axles (9.25") used the same method. link Are you guys certain he has a clutch-type limited slip?

 

Yep. it's a clutch type
https://dodgeforum.com/forum/1605035-post4.html

 

Factory LSD in a 1500 (9.25" AAM) is a friction type and requires the additive.

If not mistaken the 11.5" AAM uses an American Axle Trac-Rite true locker, which is a full locker when engaged and a LSD when not, and yes, it is friction-less...