For those with limited slip diffs I'd recommend staying away from the "NS" Redline has a 75w-90 that has the limited slip modifiers already in it, that's what I used and have had great results. The NS would have to be paired with LS additive.
PS: Yes I know it's an old thread, just felt like adding my $.02 for anyone that uses this thread as a reference. :top:
To clarify, 2005 - 2008 X-Runners have a clutch type LSD, and 2009 and later have something else (open diff with an electronic LSD?). You want the friction modifiers in the clutch type diffs, and you don't need it in the open diffs (with or without the electronic LSD feature).
As for Redline, you want to use their 75W90 GL-5 Gear Oil in your 2005 clutch type diff,
http://www.redlineoil.com/product.aspx?product=57904
and their MT-90 75W90 GL-4 Gear Oil in your transmission.
http://www.redlineoil.com/product.aspx?product=50304
If you want confirmation, or you forget which oils you need, just go to the Redline website, click the "Application Guide" tab, then put in your vehicle data. It will tell you exactly what you need.
By the way, if you use the GL-5 gear oil I linked above in your diff, you do not need any additional friction modifiers. It's good right out of the bottle.
