Originally Posted by moose308
thank you-going with amsoil severe gear?
I know it's not the answer you are looking for, but any
oil that meets the specifications laid out in the manual will be fine. If you want AMSOIL, and it shows that it meets the specs, get it.
A 2009 OR should have a M226 rear I think.
Limited slip additive is not necessary. It is not a limited slip diff.
Hope that helps.