I have an 1995 mustang automatic with 2.73 gears. I am going to put in 3.73 gears. I have two q's: What kind of differance will I see? I am pretty good with a wrench. How hard is this going to be if i try this myself?
I personally would leave it up to a shop if done incorrectly you'll be asking us where to find a cheap rear end. As far as how much of a difference it's one of the best mods you will do to your car (excluding heads/cam/or power adder that is).
Read up on this link.....its good stuff...I've done 3 FMS swaps with excellant results everytime...if your a decent wrench and have the basic tools, its pretty tit...stick with FMS gears and you should be good to go...4 or 5 of us have done at home with no probs...
The toughest part is getting the pinion bearing off..youll need a puller and press....otherwise take the thing to a truck repair shop...they have the hardware to swap over the shim and bearing...
For what it worth...with an auto most guys run 410s...I did 355s with a 5spd, drove 3yrs and swapped in 373s 2 weeks ago. i was worried about 373s being to much...373s are perfect....as they say, Dont fear the gear...you got o/drive to help out...
i did the same thing, my 95 is auto and had 2.73 gears and i switched to 3.73. it was my first 8.8 rearend swap, but i did pretty good, only because my dad had all the tools and info i needed. if you have never done it before and dont have the tools, i would suggest going to a shop to have it done. you have to have the gears mesh in properly or they wont last very long