Red Line 80301 Limited Slip Friction Modifier - 4 oz.

This thing works like magic. My LSD differential (M3 e92) started to chatter and make noise on tight turns after replacing the fluid, and it kept getting worse and worse. So i replaced the oil again and added this FM and problem is solved. However, it might be a good idea to only add half a bottle first and see if it solves the problem. I added one complete bottle and feel like the LSD locks a bit less than before (less fun :) ) so i will drain a little bit of the oil (half a liter) and add some new oil maybe the locking is stronger again.But this is perfect, i was worried the differential was going bad.

I saw a lot of info saying to use the Ford limited slip modifier for my 8.8 rebuild, but it's $70 a bottle. I trust Redline, so I bought this and used it. I soaked the limited slip clutches in it for two weeks, and installed them and poured the modifier in the rearend. The first few days I had some rubbing in the rear, but it's settled in nicely and rarely grunts. I'll definitely use it again.

Rear end clutches we making a noise in my 2010 f150Added this product and in a week it was gone.

item was as described and was delivered on time

As always Red Line is a top tier product. I use Red Line 75W90ns gear oil for the rear diff in the race car the ns in the oil name stands for Non-Limited Slip. That way I can add the Limited Slip Friction Modifier and I can fine tune the slip/grip that the rear tires get.This came from the Red Line store so I was fairly certain it would get to me on time. It was supposed to arrive in 5 to 7 days but it only took 2 days. None of my local stores had this in stock and it was going to be weeks before they could get it.