[BrianG]

I do. There is so much torque that the fronts balloon like crazy otherwise. Personally, I like 120k, but most people think that is wayyy too thick. But, I mostly bash so the extra snap is nice. 120k is just enough so you can wheelie when you want to, but more controllable than a locked center diff. For racing, you'd want more control, so thinner fluid would be better (probably around 30k).