Heavyg72

Hello all. I'm still fairly new to the forum but had a quick question on gears. I have an 06 GT Auto and have just scheduled it to go into the shop next week to have 3.73 gears installed and wanted to check with folks to see what some of the experiences have been. I currently have the C&L CAI w/93 Tune from Evolution (awesome BTW). For those of you that have done it was there a noticeable difference? I appreciate all feedback!!!

MikeVistaBlue06

Definite change with the 3.73 over the stock 3.33! I noticed it even before I had the SC installed.

Mine is wicked with the Saleen SC! I can break the tires loose at 20-30mph when it will downshift and catch 1st (with traction control off).

Good choice of gears for your automatic transmission.

Thx,

Mike

mustangman02232

stock is 3.31

tedjac06GT

I had 3.73 installed in my 06 GT Auto two weeks ago... and there is a definite increase in response and acceleration. Very noticeable! If I didn't do so much freeway driving, I'd consider going to 3.90 or 4.10 rear gears... just to get even more quickness. With the 3.73, I'm spinning about 2500 rpm at normal freeway speed (70ish). With stock gears it was about 2200. With th new gears, the car is more responsive everywhere, but especoially on starts... like sprinting on an on-ramp. I think you'll enjoy the 3.73s very much.

Ted

mac10chap

absolutely, if you are driving a lot or planning on forced induction, then i would go with the 3.73's...that is what i did but now i am kind of wishing that i had gone with the 4.10's or even the 3.90's. there is a hell of an acceleration difference, especially from a dig. however, i am now averaging around 16.5MPG vs. 17-18 from before. BUT WHO THE HELL BUYS AND MODS A GT AND THEN WORRIES ABOUT GAS MILEAGE!!!

mustangman02232

2500 rpms at 70 is not bad, these are modular motors, not pushrods, they are happy revving motors, i personally would go with the extra 200 rpms and get 4.10s for auts andn 4.30s for 5 speeds


sounds like you have leadititus, and 4.10s would be fine with a centri if you know how to drive

Heavyg72

Thanks everyone for the great information. Definately looking forward to having it done.

ddd1968rt

I think you'll be happy with the 3.73 gears. I made the switch in my '05 GT automatic, at the same time I had my other performance goodies installed (see signature). I have not had it to the track or on a dyno, but the seat-of-the-pants difference is astounding! MUCH, MUCH better off-the-line acceleration, and MUCH firmer shifts with the SCT XCal2 tune.

More importantly, if you do any kind of extended highway driving, this setup will work very nicely for you. My wife and I just got back from vacation with our Mustang. We put 1800 miles on her, at an average speed of 80 mph. Overall, we averaged just over 24 miles per gallon. The few times I kept my foot out of it, we averaged nearly 28 miles per gallon.

Keep in mind that we got these numbers doing strictly highway driving. Around town, we're averaging more in the 16 to 18 mpg range. Closer to 16 mpg if doing nothing but stop-and-go driving, and about 18 to 19 mpg in mixed city and highway driving.

As tedjac06GT said, "With the new gears, the car is more responsive everywhere, but especoially on starts... like sprinting on an on-ramp. I think you'll enjoy the 3.73s very much."

Heavyg72

All, thank you very much for the information. I just got it back this week and it's awesome! Haven't had the time to drive it very much but the pull out of the box is much better now and exactly what I was looking for.

Thanks again!!!

HeavyG!

jaiasmit

Ah shucks. Now you guys went and done it. I just got a new 06 GT Auto and and now I'm going to have to go with the 3.73 gears. I thought I could hold out a while, but all this talk is making me drool. I just ordered by C&L CAI and new tunes (for my SCT) from Brent at Brenspeed. I think I might call my dealer (who is also a large Saleen dealer, Campbell Ford) and see what it would cost to have them install the 3.73s. Thanks for the all the good input. I love this community.