On a hard launch I have a grinding noise, sounds like splines slipping in the transmission tunnel, comming from behind the center console. It doesn't slip or anything like that. I've got really sticky tires on......265 40 ZR17's in the rear. Anyone ever heard of the driveshaft spines that slide into the output shaft slipping? only does it on a hard launch and only every once in a while......First time I heard it, it scared me so bad that I lost to a damn civic(even if it was h22 powered with a 75 shot...)