I have searched all over the site and have found different answers. I have a 2005 2500HD dmax 4x4. I plan on changing the diffs to Amsoil severe gear 75w-90 tomorrow. How much will I need??

Front: ???
Rear: ???

Thanks for any help!!

I've done this twice now on my truck with Amsoil severe gear. 2 quarts in the front and 4 in the rear.

Thanks dh515!