4.10's and the auto

[matt texass]

Well it looks like the whining I'm hearing upfront is being transmitted by the d/s from the rear end. I had a buddy sit in the back seat and he said it sounded like it was coming from underneath him. I have 3.73's right now and if I'm going to replace them I have to ask about the 4.10's. What do you guys with 4.10's and autos top out at? How bad does gas mileage suck ( on the highway I get around 28-30 mpg now). It's going in an n/a car. What are yalls thoughts?

 

[SixtySix]

Well, It doesn't really "top out" at a range that I hardly ever see, so that's not really a problem. It's not too often I'm at 140+, and the car still gets there, just at a higher rpm is all.

However.... if you're really getting 28-30 mpg right now on the highway and that's important to you. Don't change the ratio.

At 80 mph I'm turning about 2800 rpms. 3000 rpm's at 85.

At that rpm my car will not get over 20 mpg. In fact, I get around 20 mpg no matter what I do, city - highway - combined, I'm right at 20 mpg.

Cruise at 90 or above and it will start dropping to around 18.

BUT

I just LOVE the way the car responds, I don't mind the decreased mileage. I'd rather have the powerband where I like it

 

[Rangersfan]

28 to 30mpg!! God I would love to have that with my commute right now. I love my 4.10's, especially when I need to pass someone real quick. My mileage averages around 18mpg.

 

[LAK3RS]

I'd make a drive down so you can check out mine, but I'm waaaayyy to lazy to do that...lol. Seriously, the 4.10's are fine for the auto. Though, I do have whine, it's not that big of a deal. I think Gearheads up in Arlington might have some of the "A" gears.

 

[MikeVistaBlue06]

Well it looks like the whining I'm hearing upfront is being transmitted by the d/s from the rear end. I had a buddy sit in the back seat and he said it sounded like it was coming from underneath him. I have 3.73's right now and if I'm going to replace them I have to ask about the 4.10's. What do you guys with 4.10's and autos top out at? How bad does gas mileage suck ( on the highway I get around 28-30 mpg now). It's going in an n/a car. What are yalls thoughts?

Look at your rpm now and multiply it by (4.10/3.73) = 1.099 to get your new rpm.

I tach 2000rpm @ 60 with 3.73s so that would mean I would tach (2000 x 1.099) ~2200rpm with the 4.10s.

You may lose some mpg. Mine increased with the 3.73s and Saleen SC with HPP tune. However, I started with stock 3.31s.

JMHO, I think 3.73s is the sweetspot for the torque curve when you're cruising on the highway. BTW at a rock steady 60 I get 29mpg........

Hope this helps.

mike

 

[Rangersfan]

Look at your rpm now and multiply it by (4.10/3.73) = 1.099 to get your new rpm.

I tach 2000rpm @ 60 with 3.73s so that would mean I would tach (2000 x 1.099) ~2200rpm with the 4.10s.

You may lose some mpg. Mine increased with the 3.73s and Saleen SC with HPP tune. However, I started with stock 3.31s.

JMHO, I think 3.73s is the sweetspot for the torque curve when you're cruising on the highway. BTW at a rock steady 60 I get 29mpg........

Hope this helps.

mike

who drives 60??? I don't think I could hold my right foot up that far.

 

[SixtySix]

That's what I was thinking.... I'm a little spoiled, Highway speed limit out here is 75, meaning I set my cruise for about 80.

60, I get up to that speed on surface streets between red lights

 

[PenguinGT]

If I had an auto, I'd probably be sportin 4.10s as well...

 

[matt texass]

i think i'm sold since I have to replace them anyways

 

[MikeVistaBlue06]

who drives 60??? I don't think I could hold my right foot up that far.

Saleen SC @ 6lbs + 400RWHP + Moderate Rain + slick ass TX limestone roads = 60mph.

I don't need any roadrash or a trip to the morgue!

 

[SixtySix]

Rain.... what this word you speak of

 

[ZmanM3]

Rain.... what this word you speak of

That is when water falls from the sky.

 

[MikeVistaBlue06]

That is when water falls from the sky.

Speaking of Georgia (of which I am a native) we have blue granite there in the asphalt so the roads ain't so slick. GA has the best damn roads in the nation bar none! I sure miss her sometimes.....

This limestone they put in the asphalt is deadly when it first rains. How can I describe it, slicker than bird shit on a hot greased griddle!

Mike

 

[ZmanM3]

Yes I am not a fan on the roads in TX. I'd say that the roads in WI are the best but along with them comes the icy roads of winter so all in all GA is probably the best driving experience, although NC is pretty good too.

 

[don_w]

I have about 35,000 miles on 4.10s with an auto trans, and I wouldn't change a thing.

 

[matt texass]

awesome

 

[Error404]

4.10's on an auto will still go 140+. I've had mine probably close to 150, on dirt.

 

[tlt05gt]

Well it looks like the whining I'm hearing upfront is being transmitted by the d/s from the rear end. I had a buddy sit in the back seat and he said it sounded like it was coming from underneath him. I have 3.73's right now and if I'm going to replace them I have to ask about the 4.10's. What do you guys with 4.10's and autos top out at? How bad does gas mileage suck ( on the highway I get around 28-30 mpg now). It's going in an n/a car. What are yalls thoughts?

What kind of gears did you put in your car? I had a problem with aftermarket gears whinning and I had to put Ford gears in to make it stop. It has been my experience that the aftermarket gears all seem to make noise on our cars.
Well I went from 3.31 to 4.10 and my gas mileage sucks at 13.9 mpg highway. It does make the car respond better but is a little damaging to the wallet. I am also running a 2.6H Kenne Bell on a built motor but even with the stock motor and gears gas mileage was not great. My car is also running 3000 RPM at 80 mph. I am going to change mine out to 3.73 and hopefully that will help a little. Good luck.

 

[matt texass]

I had the micro polished for racing m codes. When I changed the pinion flange for the spyder shaft I should have opened the rear end up and changed the crush sleeve and checked everything and got a new pinion nut for good measure. My buddies m codes have 30,000 miles on them ( I have about 8,000 miles on mine) and no whine, they were set up by the same person aswell. Maby the m codes just got me.

 

[Rangersfan]

What kind of gears did you put in your car? I had a problem with aftermarket gears whinning and I had to put Ford gears in to make it stop. It has been my experience that the aftermarket gears all seem to make noise on our cars.
Well I went from 3.31 to 4.10 and my gas mileage sucks at 13.9 mpg highway. It does make the car respond better but is a little damaging to the wallet. I am also running a 2.6H Kenne Bell on a built motor but even with the stock motor and gears gas mileage was not great. My car is also running 3000 RPM at 80 mph. I am going to change mine out to 3.73 and hopefully that will help a little. Good luck.

13.9? How fast are you going? I average 18mpg on the highway, granted you probably have more horsepower than me, but you should get better mileage than that I would think.