Now that it has gotten a little cooler, I ride with the windows down at times and have noticed that under 3/4 or more(haha..I love boost) acceleration from a stop my truck will sometimes chirp second with my 37" Pro Comps XMT, I never noticed this with the General Grabber Red Letters, man I miss those tires. It would always lay down in first but never noticed chirping second. Seems to do it more if I accelerate hard then ease out just before shift. Is this just something these trans do? The truck shifts fine and the fluid looks perfect. The truck doesn't have a tuner or any performance mod YET. Anyone else's do this???? Maybe just the tires, I don't really care for them..a little too noisy with the windows down(most people said they were relatively quiet..I guess compared to a set of swampers maybe,LOL),don't balance very well, seem to spin fairly easy especially wet roads. I think I will try the Mickey T's next, and I think I am going back to 35's.I do notice some of axle wrap, this maybe contributing to it. Traction bars are the next mod.