Caution

I'm looking at getting some new gears for my stang and I'm not all that sure how big a differance it is going from stock 3:55 to 3:73. So I was thinking of going to 3:90.Is there a big deifferance in 3:55- 3:73? Or is the differance not that noticeable and I should go to 3:90? Thanks for any advice in advance.
J

hawgman

If you are limiting yourself to those two choices, go with the 3.90s. You won't notice much difference between the 3.55s and the 3.73s. If you are willing to look beyond those two choices, go with 4.10s, for several reasons. First off, they are more fun than the 3.90s! But mostly because FRPP doesn't make a 3.90 gear for the 8.8" rear end. So that means you are probably looking at Motive gears, and they are gawd awful noisey. Don't let the fear of fuel mileage be the reason you are looking at 3.90s instead of 4.10s, if that is the reason. Going from stock 3.55s to 4.10s made a 300rpm difference at 70mph 5th gear. So fuel economy isn't going to be that much of a factor.

Caution

I was thinking the 4:10 at first but then started to stray away because I had a few people say that I would need an aluminum driveshaft as well. I'll have the driveshaft in about 2 months anyway so no big deal there. I dont know that much about motive gears but thanks for letting me know that they are noisy. How bad do the 410 effect your top end?

dkano

If your car is an auto, like mine, I would go with the 3.73, especially if its your daily driver. I've had the Motive 3.90s installed, they were noisy as hell, had them replaced with Ford 4.10s but that install didn't go so well either and they were noisy too. Plus I wasn't too happy with them since this is my daily driver, I noticed that by 30mph I was already in 3rd gear and you really had to be careful taking off from a light sometimes, plus they would have been a handfull when it starts snowing here. I had some fun with them though, but I just had them replaced yesterday with Ford 3.73s and I'm very happy with them. Plus when it comes time to get either a supersharger or a turbo I think the 3.73s will be plenty.

mail906

Is it true that Saleens as sold come with a 3:73 rear end gear? Is this true of a Saleen with an auto transmission as well? Thanks.

hawgman

Can probably assume that he has a manual since he asked if there was much differencein going from3.55sto 3.73s

hawgman

Whoever told you that you need an aluminum driveshaft if you have 4.10s was probably an aluminum driveshaft salesman....or an idiot.

How bad to they affect top end... I redline 4th at 138mph. Haven't redlined 5th yet. So I would say they don't.

mattblasi

OK I am going to settle this with a quote from a well known 05+ Performance freak who is probably one of the best suited to answer this question.

And actually if you turbo the car or use a cintry supercharger you will be better off with the 4.10s and the drivability dose not suffer a noticable amount. I also know several people running them who love them, and they are not noisy as others have said here.

Caution

About the Saleen -- I was just at ford last week and they had a few there that I was looking at while my car was in service. I looked at 3 Saleens that day and they all had 3:73 gears. My stang is a stick for the ones that asked.When you all say that they are noisy what are you referring too? Noisy as in!?!Sorry if thats a dumb question but I'm curious to what noise it makes. My car is pretty dam loud anyhow because I have an offroad X and 40 series flowmaster exhaust.... will it still be noticeable or not really? Thanks again to all -

mustangman02232

4.10s are great top end, you dont need an aluminum drive shaft, and the only gears that whine are richmonds, if installed correctly motives WILL NOT whine, i know several people with motives in all kinds of different vehicles and none of them whine if installed correctly,

5 speed 4.30s
auto 4.10s

with both, look at a 2 mpg loss on the highway and a gain if anything in the city