I got a 97 f150 with a 9.75 rear end out of an 02 f150. I am running 36 inch tsls sx with 178000 miles and the 4.6. SO as you can tell I am way down on power with stock 3.55 gears. I was talking to one of my buddies up at firestone about him helping me with an install on some 4.88s. He told me that I could not run my stock carrier with a gear that low. Is that true or not before I get my truck apart and find out that I need more parts that I dont have the money for. (I do plan on putting a detroit locker in when I have the money for it.)