2025 Mustang GT Gear Install

[Johnny_Casino]

Just picked up a '25 GT, manual with 3.55s. Car is great, but its a slouch down low.

Wondering if its possible to have 4.xx's installed at the dealer or a reputable shop. Don't plan on supercharging the car at any point.

If so, any recommendations in the Phoenix, AZ area?


Thanks.

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[Paul's stable]

Any Ford Dealer or reputable shop can do a gear swap. In my 2006 GT when I swapped in the Tremec Magnum XL 6 spd. I had 4.10's put in the rear with an Eaton posi and she is great. Go 3.73 or 4.10's would be my recommendation. 4.10's will really wake it up.

 

[Joe_Stang]

I was thinking of swapping to 3.55s from 3.15s, the car is painfully sluggish down low for having 480hp

 

[Johnny_Casino]

Any Ford Dealer or reputable shop can do a gear swap. In my 2006 GT when I swapped in the Tremec Magnum XL 6 spd. I had 4.10's put in the rear with an Eaton posi and she is great. Go 3.73 or 4.10's would be my recommendation. 4.10's will really wake it up.

That's what I was looking to hear.

Thank you.

 

[Johnny_Casino]

I was thinking of swapping to 3.55s from 3.15s, the car is painfully sluggish down low for having 480hp

Horribly sluggish. My first Coyote was a 2013 GT/manual and it felt better. Granted that car, I believe, was a bit lighter. I understand the Coyote likes to rev - just need to get it in its power band a bit quicker.

 

[RLE55]

Any Ford Dealer or reputable shop can do a gear swap. In my 2006 GT when I swapped in the Tremec Magnum XL 6 spd. I had 4.10's put in the rear with an Eaton posi and she is great. Go 3.73 or 4.10's would be my recommendation. 4.10's will really wake it up.

Agree. Had 4.10's in my former SC Roush Mustang, found them to be too much, pretty much had no 1st gear..dropped to 3.73 and that was much better, would still hit rev limiter, just not as often...........FWIW, car had been tuned to 390 RWHP

 

[robvas]

Horribly sluggish. My first Coyote was a 2013 GT/manual and it felt better. Granted that car, I believe, was a bit lighter. I understand the Coyote likes to rev - just need to get it in its power band a bit quicker.

Your 2013 had different gear ratios in the MT-82. 1:1 wasn't until 5th

 

[Mikepol2]

I went from 3.73's to 4.09's in my 2018 GT, and feel like 4.09's are are the right answer for the MT-82 gearing. Going to 4.09's from 3.55's or 3.15's will really wake your cars up.

That said, it's expensive and tuning could be an issue. Lots of labor time and some dealers don't want to mess with it. People had issues on the 2019+ when doing the swap because the car wouldn't recognize the new gears and gave all kids of weird errors. Using FORSCAN wasn't effective. A couple tuners were able to figure it out but others couldn't. So have a plan for that in place before actually doing the swap.

 

[A.alansari]

I think I read somewhere here steeda did 4.09 for the s650 without tuning

here it is

https://www.mustang7g.com/forums/th...t-has-no-access-to-tuning.160889/post-3274414

 

[Q6543]

I think a pedal commander would
Help, the factory throttle input lag is the issue,

spend a day flooring it around town, it may not be the gearing like you believe

 

[Alan Applegate]

Keep in mind, the Coyote's peak torque is at 4,600 RPM as I recall. The good part. is, it likes to rev!

 

[n_123]

I think I read somewhere here steeda did 4.09 for the s650 without tuning

here it is

https://www.mustang7g.com/forums/th...t-has-no-access-to-tuning.160889/post-3274414

This was with an automatic car I believe. Tuning is needing for a manual so is not possible yet.

 

[JohnWimsey]

Just picked up a '25 GT, manual with 3.55s. Car is great, but its a slouch down low.

Wondering if its possible to have 4.xx's installed at the dealer or a reputable shop. Don't plan on supercharging the car at any point.

If so, any recommendations in the Phoenix, AZ area?


Thanks.

Go with 3.73 gears. I have tried everything from 3.55 to 4.56s in my 12 boss. I should have left it alone and just stuck with the 3.73. I have a 25 dark horse 3.55s I think the 3.73 would be a better fit but not going through that nightmare again.

 

[Dave2013M3]

This was with an automatic car I believe. Tuning is needing for a manual so is not possible yet.

This^^^^

The 10R80 with 4.09s the ratios are already so close with the 10R80 I feel 4.09s on a street car maybe overkill.

 

[young at heart]

I went from 3.73's to 4.09's in my 2018 GT, and feel like 4.09's are are the right answer for the MT-82 gearing. Going to 4.09's from 3.55's or 3.15's will really wake your cars up.

That said, it's expensive and tuning could be an issue. Lots of labor time and some dealers don't want to mess with it. People had issues on the 2019+ when doing the swap because the car wouldn't recognize the new gears and gave all kids of weird errors. Using FORSCAN wasn't effective. A couple tuners were able to figure it out but others couldn't. So have a plan for that in place before actually doing the swap.

This would have been my first concern. Modern cars are increasingly designed to be driven as-built only, and it seems to get worse every year. I know nobody wants to hear that but it’s an unfortunate reality. I recently took my wife’s ‘24 Subie in for a slow leak in one tire. She had picked up a nail, neither near a sidewall nor catastrophic. Not wanting a suggested patch (vulcanized “boot” inside the tire) I ordered a single new tire. HA! Not so fast, kemo sabe! Turns out that the diameter difference between a new tire on one corner and three other tires with 12,000 miles of wear threw the car’s computers into complete apoplexy. Dash lit up like an ‘80s disco but in color. Required a whole new set of tires. I can only imagine what a gear change might do.

I think a pedal commander would
Help, the factory throttle input lag is the issue, spend a day flooring it around town, it may not be the gearing like you believe

I‘m sorry but I just don’t get the pedal commander thing and never will. I have a 14D on the end of my right leg that quickly handles any command I issue. It ain’t rocket surgery!

Keep in mind, the Coyote's peak torque is at 4,600 RPM as I recall. The good part. is, it likes to rev!

Yep Alan, you’re right. When in doubt drop it down a gear or two and nail the throttle. These cars are plenty happy keeping the Rs up a little.

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