GEARS

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LOL why ask, since you have already stated that you have 3.90 gears in your other post. Your first 2 post on here were asking questions, 1 about a noise you have were you stated this.....


I have a 2003 Mustang GT automatic my mods include:ACCUFAB 70mm throttle body and plenum combo, BBK CAI, flowmaster 40's, perdetor tune, motive 3.90 gears


and the next where you were thinking of buying gears.

I don't know which one is accurate, but use the search button for gears if you don't have them:D
 
ha ha sorry ment to say 3.73, previous owner had already installed them, just wondering if it would be better to go with 3.90

no prob. Just giving the newb a hard time.

No, it's not worth it. Worth maybe a few hundredths in the 1/4. Just jump to 4.10's if you want to switch gears.
 
I only did a gear swap once and used ford racing gears. everything I've always seen says that no one ever has problems with ford racing gears but I've seen alot of posts saying that problems are likely to happen with motive gears.

same about the install kits. crush sleeves are different/more difficult I guess.
 
A lot of people say their mileage isn't that bad with them. It all depends on how you drive. Me personally i'm just sticking with 3.73's seeing as how i don't drag race as often as it would take for me to really need/want 4.10's.
 
I doubt they would effect your MPG that much, maybe -1mpg....But it all depends on how you drive, and if your on the highway a lot.

Many people complain about loosing mpg going to 4.10s. But my guess would be that their loosing gas mileage because their getting into it more with the increased acceleration.

But I would guess that it would stay the same or maybe even increase it with "grandma" driving. 4.10s get you into the power band quicker without having to use more throttle; hence better MPG:shrug:

my 2 pennies
 
well i live in santa fe NM, its a small town, not really that much traffic at any given time i dont do a lot of HWY driving unless im going to work, average speed going to work is like 50-55 mph maybe, i dont go to the track that often, but there is A LOT of trans am's, mustangs, and camaros around here that cant hlep but to pull up next to you at a red light and rev there freaken engine, really intimidating, so street racing around here, including me, happens a lot, pigs dont really care either, so would the 4.10's be a good buy for me... sorry just trying to make sure i just dont want to pay for something ill regret later
 
4.10s are great I have them and they were quite a wakeup from the stockers. I don't think there wll be a big difference going from 3.73s or 3.90 to 4.10s.

I went from 4.10s to 3.73s back to 4.10s because I need the little extra bump to get me into boost faster.

One thing that will hurt you is your top end but most people don't race past 120 anyways.
 
so there is not much of a difference between 3.73 and 4.10???

Nothing huge. I don't think I would spend the money on buying and installing 4.10s if I already had 3.73s. The only reason I put the 4.10s back in was because I was having a new rearend built and told the guy to throw my 4.10s back in while he was at it.
 
I dont want to change them just because though. the gears it has now wine especially on deccelaration. I was wondering... does the wine come from the kind of gears they are and what brand they are, or is it from a bad install. the shop i take my car to is really good, so if he does a good job installing them can that prevent gear wine completly, or is it inevetible???
 
They shouldn't wine if installed correctly. I had my first set of 3.73's installed in Feb. 2006 and they never wined, I had my entire rear end built yesterday and so far no wine:nice: Some people say its brand related but others will tell you they shouldn't wine at all. I'm just glad my FRPP 3.73's(old ones, and new) don't wine
 
so there is not much of a difference between 3.73 and 4.10???

Not much, especially if you're coming from a 3.90, you'd never ever notice. I could run some calculations of what speeds you'll see in a gear, but the difference between the two depends on what gear and how high you're running it.

What transmission and gear would you like the rear gear comparisons between?
 
It all depends on the application. You dont want more than 3.73 on an auto. What will happen, also depending to your tire size, is that anything above 3.73 you will run out of gear at the track. What will happen is that you will enter overdrive and that is really risky because you can brake the band if you enter it at wot. For instance, i have 315/30/18 in the rear and if i had 3:73, that would mean i would be at the end of 3rd gear at 118.1 MPH. if i had 3:90 i would be at 113.0 MPH. I run nitrous and i trap speeds of 108-115. I would need something that keeps me in that range which would be 3:73. It all depends on your set up and what you want to have.