I want to get some gears for my car and i am thinking about 4.10s but i want to know what rpm everyone is at at 70mph? I have heard that some people are at 2400 but when i use that website that caculates it it says i will be at 1900 at 72mph with 4.10s. So i am kinda confused. What are ya'll running at in 6th gear with 4.10s? I know tire size effects it too so post your tire size too please. I am running 285/40/17 s in the back so what rpm will i be at with 4.10s? Thanks

 

Grab those 4.10's u will not regret it!! I get bout 2000 at 70, gas millage bout 200-220 a tank, great fun for the street

 

4:10's are great. Don't worry about the gas mileage. We should all be happy to be getting more than your average 20 sec SUV. my Camaro gets better mileage than my g/f's Sebring V6, so i am pretty happy.

I haven't driven my car since november, but if memory serves I am right around 2400 RPM @ 70. 245/45/17

I also get around 220 per tank.

 

At exactly 2000rpm I'm at 72mph. Thats with stock size tires. About 210 miles on a tank of gas.

 

Hehe just a thought any of u guys thought of 4.56's? I wonder what a z would drive like then ha! I might find me a set and play a lil.

 

What gear do you currently have in it?? PersonallY I think a 3.73 is the best overall gear for an M6.

 

Ditto. Gives a good gain and + the ring gear is stronger( less teeth) than the ones with the 4.10's.

 

1900 Sounds about right. Go 4.10s if you're going to change. JMHO

 

No, you are wrong. If the number of teeth determine the strength of the gear then 4.56s are the strongest and 3.23s and 2.73s are the weakest:

2.73 - 41 teeth on ring gear - 15 on pinion gear
3.23 - 42 - 13
3.42 - 41 - 12
3.73 - 41 - 11
4.10 - 41 - 10
4.56 - 41 - 9

Thats why the 4.11s are so appealing they have 37 on the ring gear and 9 on the pinion. I have pictures in my sig comparing 4.10s and 4.11s side by side and you can see the difference. 4.11s have much bigger teeth. The teeth on the 4.11 pinion gear have more of a curve to them so they have more tooth contact because they have fewer teeth.

Besides there not that much of difference by switching from 3.42s to 4.10s, I don't see why someone would only go to 3.73s for the street.

 

I wouldn't go with 3.73s unless you have a 93, if you're 94+ go with 4.10s.

 

Had a buddy who went with 3.73's, loved'em for about a month, then got used to them. Now he wished he would have gone with 4.10's. I'm going to go with 4.11's when I build up my rearend, but I'm going to put in a 9 inch. I got another bud who's going to build up a 9 inch and put 4.56's in, I'm sure he will let you all know what 4.56's feel like.
Go with 4.11's, you won't regret it!!

 

It's not about the # of teeth, it's that the thickness of the ring gear gets thinner which makes it weaker.

 

how do u guys not break rears with 4.10's?? i shattered mine with 3.42's, couldn't imagine launching on stickies with the 4.10's. Also, i can't get traction as it is, 4.10's would make me spin all day.................

 

So what are you saying? Its the ring gear that breaks and not the teeth?

If thats what you are saying then you've never seen a ring/pinion failure. No one ever breaks their ring gear, they break teeth off of the ring gear or pinion. Usually its teeth off the ring gear.

 

No one ever breaks their ring gear, they break teeth off the ring gear?

Whatever dude, think about it for a second.

Why do you think that the teeth get stripped off the ring gear?

If the ring gear gets thinner, then the depth of the teeth of the gear gets thinner as well as the teeth getting smaller. That means that there is less material there for the pinion gear to mesh into.
(The pinion gear is also getting smaller, therefore contacting a smaller portion of the ring gear BTW.)

I didn't mean that the whole ring gear shatters or something, it is just easier to strip the gears off the ring gear when you go to a numerically higher ratio.

Go compare a 3.73 gear set to a 4.11 from one of these rear ends and you will see what I am talking about.