what happens if you put in too much limited slip additive? I think i have an eaton posi ( I ordered it off ebay, and from the pictures i see on EATON's website it looks like the mechanical locking diff). Before I swaped in the disk brakes it would do 2 tire fires. but now it only does one. and I didnt touch the carrier, the only thing i did different this time is that i added almost 2 bottles of limited slip additive would that affect it?

 

here is a picture of the differential i put in






can anyone tell me what is wrong with it? when i turn the wheel by hand i see the other wheel spinning in the opposite direction, but when it locks the driveshaft starts spinning but the other wheel doesnt. WTF is wrong.

 

Looks like a Torsen to me?? A Torsen isn NOT a posi. It's a torque biasing diff. When jacked up it will act like an open diff.
I'd drain all the fluid out and try new 90w with NO additive.

 

Here's my Torsen:

But yours doesn't appear to have any clutches so the additive probably isn't required, nor does it hurt. As said above, without any resistance or lack of certain centrifugal inertia that differential probably acts just like an open unit.

 

those are sometimes refered to as the coo coo clock i believe it was the g80 code in many late model pickups. when it senses more then 100 rpm bias i believe it fully locks up until approx 40 mph or something like that.
its more useful for a truck or offroad apps.