What Fluid
We just changed out the original "clunking on turns" Torsen diff. with an EATON brand w/ Carbon Clutches.(not Gov-Lok GM type Eaton). My 3.73 gears were in fine shape, and I have a T/A Girdle so it holds a 'lil bit more Fluid in total.
I spoke to EATON tech support. They don't talk up synthetic at all over petroleum based due to the various multiple brands.
I told them I'm using AMSOIL and AMSOIL SlipLok Additive. Guy said " If it chatters change it out, if not you're good".
It's all in, and it's all good! Nice & quiet.
I did alot of research, and I bracket race this Bird too.
There are many opinions out there.
But after speaking to rear specialists and reading this, you may also want to go AMSOIL SEVERE DUTY 75/90 wt.
Check out the finer points and comparisons here. Test was independent, so can't blame Amsoil for making it available. Best Regards!
http://www.amsoil.com/products/gearl...hitePaper.aspx

