ihaveafordgt

i have an 04 gt ..auto with borla cat and CA and was really looking into getting gears 3.73, 3.90, 4.10... i wanted an opinion on how much quicker it would get and how much difference each one would have... i drive a lil over an hour 3 weekends out of a month to go home from college ... basically i want 4.10s but A. would it completly KILL top speed? B. would it get so bad mpg on the drives to and fro...?
Thanks

WhiteFoxGT

4.10s are a perfect setup for your car as is. As long as you dont plan on runnin nitrous or f/i at a dragstrip.

4.10s or go home

devongarver

See my sig....

Get the 4.10s...I have em and don't regret it.

ihaveafordgt

but i still have 3 hour drive every weekend.... how much worse would the mpg be from 3.90 to 4.10?

sharpshooter33

What comes factory on the GT in 03-04?
Anybody know the RPM's for 3.90 and 4.10 at 60mph?

ihaveafordgt

i would like to know that too.... :/

Z28KLR

You have an auto, so it will be different than my cruising rpm's, but at about 83mph in 5th gear my engine sits at 3K rpm's (60 is probably like 23-2500 or so). You'll be fine on long trips with 4.10's; I've driven from Los Angeles to Seattle, straight through (about 21 hrs. each way) a couple times since doing these gears and avg. about 25 mpg the whole way. @ sharpshooter; stock gears are 3.27 from 99-04 years.

devongarver

As said above, stock gears are 3.27's. Forget the 3.90, get the 4.10's. Here is a gear calculator. You can enter your tire size and transmission and see what enginer rpm and speed you will be at in each gear with different rear end ratios. Lots of guys on here getting 24-25 mpgs highway with 4.10s and manual tranny. for an auto, maybe 1 mpg less.

ihaveafordgt

Thank you! ill look into the 4.10's then but.... wont i top out at like 90...?

Z28KLR

^No, you shouldn't even be close to topping out at 90mph. I had mine up to 130 for a minute on a recent trip back from Vegas (real nice pull from 100 to 130) for just a sec; I don't recall looking at the tach but I know it was still below 5K.