So I seem to run my boss at the drag strip more than the road coarse. I run ET street bias ply, when trying to do a burnout I can only get the right side to spin, I always notice this in my mirrors and the horrible grinding noise that I hear, once I launch I have no issues both wheels are spinning. In previous cars I would get the one wheel wonder randomly but never the noise I am hearing now. My question is what have you guys upgraded to or what differentials are you running. I do not have the torsen. I may be able to get this replaced under warranty as I know a mechanic at the Ford dealership, or should I just stick something else in? I plan on drag racing it, and still road coarse and a few auto cross events. I am leaning towards the tru trac, and really don't know if the torsen is worth twice the money as the tru trac. What do you guys think?