i got a 02 gt .with a intake, american tunder catback and 373 gears. when i got my gears installed i used a sct tuner(the one with the loaded tunes)i first used the 93 tune and did noting but set it for 373s. i then toke the car for a drive and noticed that when i was just cruiseing if i would go even a little wot it would make a clunk(sometimes its more then one clunk in a row) that comes from under the car. it does not do it in park or if i run the car with the stock tune. the car runs fine idles like a champ but that nosie is killing me does any one have any ideas as to what it can be its an auto with 74000 and when i bought the car 2yrs ago ford replace a tailshaft housing and troqconvert or so they say cause it was under warrenty.