I don't know how well Phil oil would work in a cold environment. FWIW I typically run 30 weight in mine, but live in the deep south. One time we hit the high teens for a couple of nights and the hub was very balky. I know that people that live in places like MN use lighter (10wt) oil if they plan on riding in the winter.

IMHO the key is to A) use oil and B) not use a vegetable based oil.

Aaron