first, sorry if this has been discussed before, im still new to mustangs(7/13) so I haven't been around for much of the discussions. But I did do some research, theres a lot of back and forth info out there so I need some more help.

Im looking at what my next mods will be, currently im leaning towards eibach prokit suspension, or roush upper and lower grilles and few other appearance mods(minor), or gears. My question is not about which mod, but specifically GEARS. they seem to be the best bang for your buck

my main concern is mpg loss in the city. almost ALL my driving is city driving. so ive seen many reviews and looked on forums, and it seems that the mpg losses are mostly for highway driving, and/or driving style. SO, assuming the driving style is the same, and that style is for max mpg's/smoothness, are steeper gears actually BETTER in mpg than stock?
and if so, which gears would be best 3.55, 3.73, or 4.10?
right now im leaning towards 3.73, but from what ive read, people say theres a difference in what you get between a manual or auto. ive read stuff like, where in a manual 3.73's are great, in an auto, its better to go with 4.10's to get the same kick as you'd get with 3.73's. im a noob at this, so i'd like some help

another confusion ive seen even regarding the highway mpg loss, is most of those things I read were for 5 speed cars.. since mine is a 6 speed, would I still suffer as much even on the highway?
also forgot to mention, ive heard about gear whine. what can I do to prevent this? or is it inevitable?

ive learned quickly how to be soft on the pedal(used to drive a prius anyways lol), and I love having more low-end torque. it'd be awesome to be able to get more mpgs, more low-end torque, and more fun!! that's what im doing right now.. to/from work, max mpg driving style.. but on fun runs, max fun style but I need some more kick for those fun runs lol.

 

With gears your mpg loss will be at speed on the highway more so than city driving.

 

Go with 3:73 gears and call it a day. You will love them. !

 

that's what I want to do, but after reading some comments that the 3.73's aren't as much of a kick on automatics as on manuals. even the AM guy I emailed flat out recommended the 4.10's because of my car being an automatic(and of course because I told him I very rarely do highway driving).

do you have an automatic? and do you know about how big of a difference in mpg 4.10's will make? im just very curious and am im trying to get as much info as possible before making a purchase. thanks guys!

 

I have an automatic and love my 3:73 gears. I think if you go with 4:10's you will be thrilled and love there performance. If you get 3:73's you will be thrilled and love the performance. Either way its gonna be huge over your 2:73 gears in there now. I'm sorry but don't know how much less mpg 4:10's get compared to 3:73 gears.

The only real issue I could see having 4:10's is when you nail it from a dead stop, how much tire spin are you gonna get? That would be an issue because you ain't moving forward if your spinning. Lol

 

I don't mean to jack your thread by any means roadrunner but I had 3.55 in my '12 6MT and loved them best combo for mpg and performance for the V6 imho. I now have a '14 6MT with 3.31 & I'm wondering about gears also. I'm wondering if I should upgrade to 3.55 from 3.31 which most have told me it won't be worth it and to go for 3.73 but my driving is 50/50 city/highway. Suggestions?

 

You know my stance, lol but I have an automatic not manual so people with manuals may feel different.

 

go with the 355

 

go with the 373's

 

go with the 410's

 

no but really I would go with the 373's its a happy medium

 

My tires have tons and tons of grip though.. But your right, 3.73 should make a big jump for me. Thank you very very much!! Coming from you with a similar car helps bigtime, thanks again

No worries

The people have spoken... 3.73s it is! Thanks!

 

I would say the 3:73 gears would be on the happy higher not medium. 3:55 would be more of a happy medium. Lol.

 

Glad I could help bro. I assure you will not be disappointed with the 3:73 gears. You will think you gained 100 HP with them. On a side note, did you say you had a performance tuner, if not you might want one to speed caliber the new gears.

 

3.73's are just fine, came with my track pack and still get 26 mpg. Don't fear it!

 

Yeah i have a bama tuner. So far i havent done much, just AirAid CAI, Borla S-type AB's, and of course the tuner.

Wtf? 26 on a GT?? Nice!

 

I have a stick with 3.73s. I got the gears installed almost two years ago. If I keep the car under 75 on the highway, I can get between 28-30 mpg. A lot of it comes down to tuning and other mods. I've got a CAI, TB, ported manifolds, shorty headers and full catback as well as an aluminum DS. My Bama tune could get me 30mpg with those mods, but since I've switched to MPT, I'm getting low 29s.

Depending on how mpg conscious you are, if I had an auto, I'd get 4.10s. However, I'm pretty sure, you'd only manage 24-25mpg.

General rule of thumb I've observed so far for gears on our car with street tires:
2.73s=14.0 second 1/4 mile
3.31s=13.7
3.55s=13.5
3.73s=13.2
4.10s=13.0