About 3000 miles ago I repacked a slightly noisy CV using Castrol Syntec 
grease.  The joint was not staying quiet despite often injecting fresh (but 
cheap) moly well into the balls/cage with a grease gun.  The Syntec is a 
lithium based, not molybased grease.  It has seen town driving and a couple 
of 500 and 200 mile@ steady 75+mph trips, and in pouring rain / heat. It's 
also been well abused Syncro style, and is the front axle.  

The point you ask...So far no problems, absolutely silent running.  Seems 
like it works fine, I'd phoned Castrol tech line and they said it would 
yada.. Still costly grease compared to my local hardware/car store prices, 
but about 1/3 of the price of those little 90 gram packages the FLAPS and 
dealer sell. Took 2/3 of 454gram tube for a really well packed axle, 
including the face of the trans flange.  Cost was $5.40Cdn.  I have noticed 
that the old cheap moly grease that gooped out while rebuilding has 
literally washed off over the summer, not a good sign.  Plus my shift 
linkage works better now with Syntec than when larded with this 
dissappearing moly stuff. Other opinions/thoughts welcome.  Tim Smith

cheap trick by old VW mech, buy the cheap grease and one little packet of 
good stuff. Rebuild with good stuff on balls (the CVs, idiot), cage and 
bearing faces.  Then smother in cheaper grease and pack the boots with more. 
 This keeps the good stuff from spinning off/protected from water leaks.  
from the garage of Mr. JBWeld Inc.