In my last conversation with Daryl on the subject, he held that for stock torque type motors, any off the shelf synthetic 75W90 gear oil would be fine.  The exotic lubricants are necessary for higher torque applications. Stock motor? GL5 synthetic. Subi  or TDI powered Syncro? Something better. Swepco 203? 205? was mentioned. 091 gearbox? You can get what you need at your local chain auto parts store.

My diesel and the ABA powered A�wagen both have full synthetic Valvoline in them. 

Jim

On Jun 21, 2014, at 7:57 PM, Mark Tuovinen <aksyncronaut@GMAIL.COM> wrote:

> Daryl stopped recommending Redline a number of years ago, if I recall
> correctly he understood that they had changed the formula and he did not
> feel the new version would provide the lubrication and protection necessary
> for our transmissions.  I did speak with him about alternatives and he was
> fine with Swepco especially for the higher horsepower crowd, he also said
> that Amsoil would be ok, was not sure about Royal Purple but only for lack
> of knowledge with the product, and had no comments I can remember other
> brands on the market.
> 
> Mark in AK