guys with 4.10s get in here

[fastgtfairlane]

i was at a friend of mines shop the other day. he rents a big shop and has someone that runs his own business and they share a building together. anyhow the friend does 4x4 mods and can and does just about everything. this guy has all kinds of tools from breaks, presses and a tig welder. i was talkin to him and he had several ring and pinion gearsets laying around. i asked him if he had anything for an 8.8. he happened to have a 4.10 gear set with a trac loc 31 spline carrier that he will give me for 50 bucks. my question is this, will 4.10s be too much gear for my mild setup? what are some round about rpms u guys are turning at highway speeds? i have 3.08s now and would like some 3.73s but the 4.10s are way cheaper and appear to be in good shape. fellas give me some suggestions on it and would you get the 4.10s over the 3.73s. im eventually gonna do some more serious mods to the car i have a new engine to build for it in the future. btw my current mods include a full exhaust w/ e/l shorties, x pipe, home made cai, mild ported typhoon u/l manifold, 65mm tb, 24lb injectors, pullies,. msd box. and the car is a 5spd.

 

[Pokageek]

Ford Mustang: Mustang Tech: Calculators & Decoders: RPM Calculator

Go there and put in what you like. Don't fear the gear and have fun with it. The most fun gear I had was 3.90's.

 

[desertcox05]

i've got 4:10s with stock motor and a 5 speed. i wish it really had the 373s instead, 1st gear is basically useless for the street. rpm's are about 3k at 75

 

[fastgtfairlane]

at 80mph according to that calculator there is a 300 rpm difference with the same tire between the 3.73s and the 4.10s and a 900 rpm between the 3.08s and 4.10s. how much did gas mileage change when u switched. i drive my car daily and will probably get a job where i will be driving 100s of miles a day. the plan is to get another car and make the mustang a weekend car really soon. im really thinking about getting them.

 

[tstang21]

its hard to say about how your gas mileage will change according on how you drive. im looking forward to swapping in 373s and i drive mine daily. in addition i control myself and drive slow like a vette driver. 100 miles a day seems alot. i like 373s for daily driving. 410s seem to be radical for regular daily use. 410s are great though but i could them mostly on auto tranny.

 

[BREWTUS428CJ]

Run It! The difference between the 4.10 and the 3.73 will be about 300 r's at 70. At 75-80 I'm around 27-2800, so 4.10 would be around 3100 or so.
How much time you spend on the freeway?

 

[fastgtfairlane]

well hopefully my car will be driven daily for a temporary period of time as gas will and is already costing an arm n a leg its hard to turn down the 4.10s for 50 bucks. i would also like to get the 31 spline trac lok differential thats with it.

 

[hollywoodstang]

Well i have 4:10 gears and i am going down to 3:55.

I thought about going 3:73 but there is no point going 4:10 to 3:73. Personally i think 4:10 is too tall for the DD.

I drive on freeway a little but i top out too fast with 4:10.
If you have 4.6 with auto 4:10 makes more sense. so i am taking out my 4:10 and putting it in my 4.6. Iif you are not a hardcore drag racer 4:10 will be only good for stop light to stop light race.

Don't even worry about the MPG. You drive a mustang... if you want great gas mileage get one of those 35k toyota electric car. I dont even know the name...

Anyways. Remember on a freeway if you have 4:10, camaros will fly right by you. This happens to me alot. I top out on 5th and i have no where to go. I will be at 5500rpm on 5th gear!

By the way i have more little more MODs then you do so that's another reason why i am going down to 3:55.

I have brand new ford racing 3:73 gears in box i am selling due to this reason. if someone wants it let me knowGood luck !

 

[GRGT1994]

I can give you the opinion of someone who has run both 3.73 and 4.10 in the same car.

My first major mod was 4.10 gears. My rationale was that that was going to be the only mod I would ever do, so why not go all the way. Of course that didn't work out the way I planned. And soon I had the TFS top end kit, full supporting mods and suspension mods.

Well at that point, I had definitely gone too far with the 4.10 gears. They were perfect for a stock 5 speed. But with the added go of the H/C/I kit, 4.10's were just ridiculous. I went back down a notch to 3.73.

I like the 3.73 fine.

Take that as you will. But I'd say that the first thing you need to consider is you car. Auto or manual? Because many say that a 3.73 on a T-5 is equivalent to 4.10 on a slush box.

Then beyond that you need to figure out where you might go with the car next. If this is truly the last mod, then go with all the way. If there is a chance you will do forced air, or stroker or other major power upgrade, I seriously consider delaying the gear change until you sort out the rest of it.

The stock gears suck, and you'll be far far more happy with the 4.10's than stock, no question. But labor is more significant (even if you are doing this yourself) than the cost of the parts - especially for you. So you'd be better off waiting if there are other changes in your near future.

 

[Pokageek]

YEa, get the gear you want and dont think about $$. Personally, I think 3.73 is perfect. Like I said, I am glad I went 3.55 cuz I would have less traction than I do now with 3.73. BUT I am going to be closing in on 450na rwhp and a STREET car with real good low end - which means spin withut DR's. With a h/c/i car or stock I would go 3.73, especially if doing HWY miles.

4.10's yes you will be rockin everywhere but HWY where you will be passed (on a closed course of course).

 

[sprintertech]

4:10's with 295/35/18 bfg d/r's @70 im at 2700.....car went best of 12.67@106 with 1.59 60ft.......and also has no prob pegging the speedo.....but i will say the 4:10's are a little much for a dd but i do it and wouldnt even think of changing them plus the price you mentioned aint bad at all

 

[final5-0]

im eventually gonna do some more serious mods to the car i have a new engine to build for it in the future. btw my current mods include a full exhaust w/ e/l shorties, x pipe, home made cai, mild ported typhoon u/l manifold, 65mm tb, 24lb injectors, pullies,. msd box. and the car is a 5spd.

A different line of thought to think about here

True ... gears on the highway are simply about doing the math

However ...

Steeper gears on a Stock Stang
and
A Stang whose power band has been extended

Well they are as different as night and day :Word:

Think about how a Stock stang starts to peter out just before 5K

That has a lot to do with why some peeps complain about a short 1st gear

When you can pull to 6K or a bit above .......
373's will seem quite tame
and
Some ... like me ... kinda wished for the steeper 410's

Also ...Not only will your power band be extended ...
It most likely will be shifted upward
and
It could be shifted up a good bit depending upon combos parts chosen

Now if talking about a Stang that is serving as a DD
that could be different as opposed to my weekend only toy
so ...
You might not wanna go as steep with such an application

Grady

 

[fastgtfairlane]

i really wish the 4.10s were 3.73s but it is what it is. atleast i could get a 31 spline differential with it for 50 bucks. i think im gonna go ahead and get it. i could then build my engine to have a little higher powerband.

 

[final5-0]

Forgot to tell you another way to make the 410's less radical

Just run a taller tire

Grady

 

[Pokageek]

4:10's with 295/35/18 bfg d/r's @70 im at 2700.....car went best of 12.67@106 with 1.59 60ft.......and also has no prob pegging the speedo.....but i will say the 4:10's are a little much for a dd but i do it and wouldnt even think of changing them plus the price you mentioned aint bad at all

...Well...got news for this post. ..with those tires you really don't have 4.10's compared to someone with normal size rims. You have more like 3.90's. Apples to apples.. that is.

"When you can pull to 6K or a bit above .......
373's will seem quite tame"

No way, lol. But that's me... Sorry but I bug fat disagree on that one.

 

[sprintertech]

...Well...got news for this post. ..with those tires you really don't have 4.10's compared to someone with normal size rims. You have more like 3.90's. Apples to apples.. that is.

"When you can pull to 6K or a bit above .......
373's will seem quite tame"

No way, lol. But that's me... Sorry but I bug fat disagree on that one.

i see the point your trying to make....but the tires i run are only 26 tall.....the mph as opposed to the rpm still stands....but you are right tire height makes a big diff and....but he didnt post his tire height

 

[fastgtfairlane]

right now i have 245/50r17s in the rear but will be buying new tires really soon. im thinking about getting new rims with 10.5s in the back and a 315 in the rear.

 

[sprintertech]

so your tires are actually taller then mine being closer to a 27 tall tire........

 

[fastgtfairlane]

yeah but there is absolutely no tread left on them at all lol. new tires are in the works asap.

 

[gunfish]

I went to 4:10's from my stock 2:73's. My car is a stock aode DD, my commute is 30 miles a day, 28 miles street and 2 miles freeway. I changed my gears about 3 years ago, and I haven't noticed any difference in mpg.
Unlike a lot of others here, I don't really race or drive my car hard often, but when I do get on it I'm glad I went with 4:10's.