I have a 06 Audi A4 that I bought not to long ago. And one of my "things" that I do when I purchase a used car, is change pretty much all the fluids. I actually already changed both my Gear/Front Diff oil (they are shared) and rear diff. Both with RP 75w90. Let's just say, that I should have done more research. RP claims it is safe on yellow metals, which is fine. It is that now my shifting is not nearly as smooth. So I think I will be ok with leaving the RP in the rear diff, but I need to do something about the front and quick. I live in Anchorage, AK. So it can be kind of hard to find certain products. No Redline/Motul/Amsoil (well maybe on the Amsoil going to check a certain shop tomorrow). The OEM fluid is crazy crazy expensive, so I would like to at least try to find an alternative. I did find Lubro-Moly at NAPA, but it is GL5. Any help would be great, I plan on changing it out this weekend.