He guys can you dumb down a little for me. You guys are way beyond me with trying to improve the mileage, speed etc. I am just trying to see what it would take (if parts are available), to fix my M920. The problem I have is that when I went to pick it up, the fluids had been drained in engine and transmission because of EPA concerns with leaks. We got a wrecker to roll it on the low boy trailer (brakes were already caged), back end first. As the rear wheels were going on to the trailer, we heard a loud pop. The pinion gear shaft broke just inside the seal of the differential. Aside from trying to understand why it broke, what are my odds of finding the parts to fix it? Who would I check with for parts availability and cost?