I use Lucas Oil in my differential and transmission, but I am starting to hear bad things about Lucas. So what do you guys use, and whats a better product?
Amsoil, Redline, Mobil 1, Castrol ... have good synthetic gear and trans fluids. Mobil 1 and Castrol can be found at almost any auto parts stores, Amsoil and Redline are mostly online.
I wouldn't use it personally but I wouldn't tell you to run out and change it. Amsoil is no joke when it comes to gear oil. If you really want to baby your ride I would go Amsoil, but every fluid HTSS_TR mentioned is good.