Gear ratio swap questions

[AppoTheApple]

Hi,

I am looking to swap my GT's gear ratio from my stock 3.15s to 4.10s and am curious as to what all I need to purchase for this. Aside from the gears, it sounds like I need a tune, but is there anything else that is required?

And any recommendations on things that aren't required but would be helpful. This is my first mod I plan to do when I get my tax return, soany advice helps. :cheers:

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[Coyote Red]

The S550 has to also be adjusted with a special tuner for gear swaps. I can't remember the company name that has this new devise, someone chime in and help me?

 

[Terminator2]

Hi,

I am looking to swap my GT's gear ratio from my stock 3.15s to 4.10s and am curious as to what all I need to purchase for this. Aside from the gears, it sounds like I need a tune, but is there anything else that is required?

And any recommendations on things that aren't required but would be helpful. This is my first mod I plan to do when I get my tax return, soany advice helps. :cheers:

4.10s in an auto? Why so steep? Whipple flare tool is needed to reflash the bcm for the gear change normal tuners cannot access the bcm only the ecm.

 

[AppoTheApple]

4.10s in an auto? Why so steep?

Everywhere that I've read said that those were the recommended gears for an auto. From a few forum posts from other sites to American Muscle's gear ratio guide. Is that not the case? What would you recommend? I'm open to all suggestions as I'm still pretty new at this stuff.

 

[Terminator2]

Everywhere that I've read said that those were the recommended gears for an auto. From a few forum posts from other sites to American Muscle's gear ratio guide. Is that not the case? What would you recommend? I'm open to all suggestions as I'm still pretty new at this stuff.

The A6 has a very aggressive first gear and overall pretty aggressive gearing compared to most old school autos. It depends on how you use the car and what mods you want to add (cams and high rpm manifolds especially) but 3.31-3.55 seem to work very well on the auto cars. The fastest auto NA S-5500 is on 3.31s he has tried up to a 3.73 I believe but he's faster on 3.31s. If you do all city driving and only car about perceived acceleration you could do 3.73s but your first gear would be insanely short.

 

[AppoTheApple]

The A6 has a very aggressive first gear and overall pretty aggressive gearing compared to most old school autos. It depends on how you use the car and what mods you want to add (cams and high rpm manifolds especially) but 3.31-3.55 seem to work very well on the auto cars. The fastest auto NA S-5500 is on 3.31s he has tried up to a 3.73 I believe but he's faster on 3.31s. If you do all city driving and only car about perceived acceleration you could do 3.73s but your first gear would be insanely short.

Got it, thanks. That's very helpful. I do about 50% city, 50% highway. Do you think an upgrade to 3.31s or 3.55s would be worth it?

 

[MoneyPit#53]

Speedo can be corrected pretty easily by using a wifi obd2 adapter and using the FORSCAN software.

 

[gameovergt]

I have 3.55's in my auto & feel they are perfect.

 

[Monopoly]

+1 for 3.55s. im also 50/50 hwy/city. works really well.

 

[stang1971]

will need a complete new diff housing.... the 3.15 housing will only work with those gears.... nothing else will fit.

 

[SVT Wylde]

I posted the question of swapping from 3.15 gears to 3.55 gears and the general consensus was it won't make a big difference considering the cost and a converter would be a much better investment.

Im keeping the 3.15's and buying a 4C converter and headers.

 

[Terminator2]

will need a complete new diff housing.... the 3.15 housing will only work with those gears.... nothing else will fit.

Yes that's correct you will need a different housing. A different torque converter and 3.31-3.55 would make a difference for sure.

 

[EcoSwag1990]

I've been looking to swap with someone for a while myself. I know somebody with a blower needs these 3.15s

 

[Need4Speed15]

This was discussed just last week...

http://www.mustang6g.com/forums/showthread.php?t=74332

 

[CCCP1999]

4:10's would be nuts.

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