clowe1965

Several people have complained about 1st being too short when switching 3.73's on the manual transmissions; since the automatic has an even steeper first gear ratio I would rule out using the 3.73's and stick to the 3.31s since you are also concerned about MPG on your other thread.

Warrio17

The 3.73 are very short. I have the manual. I'm typically through 1st very quick, not so much because of the gearing, but because I'm doing my daily driving and not racing my car and trying to conserve fuel. I love my gearing, I however live very close to my work and I don't work about mpg or related fuel cost. "Pay to play" I would check out the 3.55 if I was you. Anything is better than stock, determine your goals/ desires and don't go back, its always better to error on the high side.

scottmach

The best gears for the autos are 3.31's, especially if you want good numbers at the track. Anything more will have you shifting into 4th before the stripe. Personally I like my 3.15's. They've been good enough to get me a 11.7 on street tires.

mustangergt

http://editiondigital.net/publication/?i=88199&p=142

This link shows you can change gear ratio's as the Ford Tech said.