hey guys, just a few questions. if i buy a posi diff. and 3.45 or 3.73 gears for my 01 v6 (i'd love to get 4.10s..but i hear they drop gas mileage) what else would i need to buy? and if you've done it with your car before, how much did it cost to install, or is it easy enough to do yourself?

 

first what u have a auto or stick?

 

its an auto.

 

you need: 4.10's for auto. Those are the only two gear ratios available for the 7.5'' rear end(3.73/4.10). You will need a tuner for an auto to recalibrate your speedo. Install can range from $250-400. You should also buy the rear end rebuild kit, just as an insurance policy that nothing goes wrong. Read the gear thread!!! https://mustangboards.com/general-te...ar-thread.html

 

alright, thanks dude. just one thing, i found a website that also carries 3.45 gears for the 7.5. i know i shouldnt use them now, but just thought i'd share.
http://www.brothersperformance.com/c...oducts_id/1747

 

wow, I have never seen that ratio for the 7.5. I wouldn't even be worth it though considering you have 3.27's stock.

 

really? i thought i read somewhere that sixers came with 2.73s stock, but whatever.
another question....I know that 4.10s are the best performance wise, but is it true that they decrease your gas millege? its a small concern for me, so in that case would 3.73s work better, or can autos ONLY have 4.10s?

 

4.10s or 3.73 will work, 4.10 will make you gas millege go down. get the 4.10s over the 3.73 becouse it will put you back in your set a little more then the 3.73.

 

alright, thanks for the imput guys.

 

the 94-98 V6 stangs came with 2.37's the 99+ got the 3.27's

 

That 3.45 gear ratio you were seeing was probably for the Chevy 7.5". I think that's the gear ratio my friends v6 camaro had.