over the weekend me and my dad who are both mechanically inclined, decided to throw 3.73's in my stang. its an 06 gt auto. the tear down was easy and nothing was damaged. car has 86k on it. we have all the special tools and goodies to properly complete the task. our first problem was that the pinion with stock thirty thousandth shim on it, would sit too far in the pumpkin and hit the carrier. so we took it all out and used the stock bearing with the center grinded out to get an idea of how big of shim we needed. so we went with no shim on the pinion and therefore the fitment seemed perfect. with everything in and the gear shimmed right(or what we thought was right accorinding to three different books) everything seemed to be perfect. so we get it all back together and fluid in it, let it run at idle with it on jacks for about ten minutes, got it off jacks and took it for a test drive, literally around the block no faster than 20 mph and right away we heard the infamous whining, and when i let off the gas it was kind of a clunking sound like once i let off the gas and the pressure wasnt there