That's a good question. I know it's out there, but I'm not real sure where to get it. I will look into that. What I do know is, I am running a w series, and the last thing I am is easy on my rock truck. I have had no problems, I'm running front and rear welded diffs with dual ultimate crawlers, the motor is super strong and I have had no problem. However, I had a w series in my driver which has a chevy 4.3 that is very healthy, it through down just under 200 ponies on the dyno with 37's, I blew two of them up before I went to the th350.
