<VV> Tranny/diff fluid levels

[Frank DuVal]

>The simple thing to do is add the additive.  The experimental thing to 
>do is test the positraction torque (I vaguely remember 300 ft lbs, but 
>others more current may know better) with the diff cold and warm to see 
>if it is in spec without the additive.
>
>With respect to diff oil.  Modern 8Xw90 differential oils are usually 
>GL5.  This stuff has sulfer compounds that eat brass syncros when the 
>oil is very hot.  If your oil never gets hot, then no sweat.  Otherwise, 
>  a sulfer-free type is better.  Redline makes some suitable stuff, 
>forget which name, as do Audi directly, as quattros have the front diff 
>and tranny connected.  Presumably, GM also specifies a suitable brew. 
>Don't know about Amsoil.  :)
>
>kirby
>  
>

So if the GL5 sulpher compounds are added to make the lubricant hypoid 
rated, what are you doing to your ring and pinion gears, that are hypoid 
in a Corvair, if you do not use a hypoid rated lubricant? In real road 
tests of  over a half million standard shift Corvairs, how many synchros 
have been eaten by hypoid lubricant? Not all cars have been made with 
hypoid ring and pinion gears, hence they do not need hypoid lubricant.

Frank DuVal