The stock oil in the Savage shocks is indeed 10 weight. The stock shocks are also pretty darn weak. I would not go much above 35 weight oil/silicone in the stock shocks.
I upgraded to a set of Hot Bodies all aluminum shocks and ran 60 weight silicone and got good results, but was still not happy with the springs (weak, weak, weak). I ended up dumping all Savage shocks, buying the New Era Models upper A-arms that allow the Savage to take T-Maxx sized shocks. I now run with a single Mugen Seiki MBX-2 rear big bore shock on each corner with a Kyosho white spring. This Savage now handles everything I can throw at it, and the shocks are fine. I am running 30 weight in the front and 35 weight in the rear.
This gives you another option to explore.
Let us know what you do and how it turns out.