well I have torn the HF apart. I believe its the center diff. Everything has been gone over with a fine tooth comb. The center diff is the only thing left. I'm going to go do that right now. It's 11:17 pm here and I have to rebuild the rear diff in my ofna gtp, center diff in my HF, and the rear diff in my 18t. Along with repairing a rear arm on my tc4. And if I get time finish up a Hot bodies LSP roller for my friend. Work sarts at 10:00 AM and racing starts at 1:00 pm. I work for the hobby shop that I race at so it works out just fine. I might just pull an all nighter and red bull and monster my way through tomorrow. The wife is asleep and I've taken over the kitchen table and floor.