my tranny/diff UOA, let me show you thems
 

In case you aren't familiar with the setup, these came my black turbo car. ~2000lbs dry, 350whp, 295wtq.

~100k mile '99 6-speed, put into service in this car ~7/2010. Approx. 15 hours on the trans/fluid in this application. I expect transmissions to last about 18 months in this car. Fluid is Amsoil 75w90 MTG GL4 - this fluid is awesome and we use it in everything.

https://www.miataturbo.net/attachmen...chmentid=20219

Diff is an unknown mileage 3.909 Torsen, put into service a long time ago on this car (like 2008 sometime). The outrageous copper content is a little unnerving. This is Redline 75w250 Heavy Shockproof (helps keep the thing together during constant shock-loading due to inside rear wheelspin). I may try an Amsoil product here too after the next change in December.

https://www.miataturbo.net/attachmen...chmentid=20218

For your pleasurez.

Holy calcium in the diff!

Thats some very good info to share. I should send off my trans oil and diff oil off in the next 15-20k miles on my DD. It'd be interesting to see results of a street driven car like that compared to yours. I use redline 75w90 trans fluid and Mobil 1 LSD diff fluid.

My dad has a big-ass book full of UOA tests with mobil 1 when synthetics started getting bigger (can't remember the date lol) I'll have to track the book down.

Thx for the info!

How much do these tests cost?

Not expensive. www.blackstone-labs.com for exact rates.

Andrew, switch to the Amsoil 75w90 SevereGear.(SVG) That's what I use in my Cusco clutch type diff and in Torsens. I called AMSoil right after I got the diff, 2 years ago, and spoke with an engineer. He told it was the best they had for race applications and he said it had a friction modifier in the oil, as well, which works good with the clutch type diff. I took his word for it, but don't have any conclusive data to back it up. My diff has always worked properly.

http://www.amsoil.com/storefront/svg.aspx

I will pull the Shockproof in 3 months and switch to SVG. Thanks wagz.

OS Giken says to use their special LSD lube, and I am. But at $45/liter - is it worth it?? I'll have to take a sample when I change for comparison next time. I didn't want to risk destroying $1500 of awesomeness.

I also run the Severe Gear and contrary to popular belief, I am not a homosexual.

Of course they do.

Question is - will you after buying one?

Their FAQ has me rolling!

http://www.blackstone-labs.com/faq.php

best faq ever.