4:10's on the highway??

EPIK

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Jul 3, 2004
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I know this question has probably been asked hundreds of times on here, but I need a solid answer so I had to ask again. I really want to swap out my factory gears in my 03 mach 1 to 4.10's. The probem is I like to cruise at 75-80 mph on the highway. Basically my question is where exactly will my rpm's be cruising at 75 mph. I have been getting mixed answers ranging from 2500-3500. If its 2500-2800 I think I could take that, but 3500 is a bit high to me. My rear tires are 295/35/18. Plus I plan on doing a procharger in the next year or so. Am I better off going with 3.73's, or is that just a waste of money going from 3.55 to 3.73's? I wish i could ride in someones car that has 4.10's, then I would know exactly how its gonna be. Unfortunately none of my freinds own stangs. I know this sounds like a newbie question, but Im not a newbie. I just have never done gears in any of my stangs yet... Thanx
 
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Ok. So I researched, and found a RPM calculator that said at 75 in 5th, with 4.10's I should be at about 2450, and at 85 I should be at about 2750. Does this sound right ? Sorry for asking this redundent question, but I dont have wads of $$$ so I like to only do mods once. I wouldnt want to get 4.10's and find out they were too much. Or get 3.73's and not feel much of a difference. Even though the car is not my daily driver, I still want to get out on the open road and cruise. And I do want to do a little bit of drag strip duty, but mostly just be able to terrorize cars on the streets. For now I just want to be able to take LS1's till i get my blower. Then it's C5 Z06's, terminators, and STI's ETC..
 
People have forgot you could always get 3.90's instead
if you don't like the high rpm's and bad MPG.
The rpm calculator is right on the money.
I had FRPP 4.10's in my old GT and I didn't like the high rpm's
on the highway either.I also got bad MPG and I was putting
gasoline in my mustang more than I wanted to.
Motive or Pro50 3.90's are a good compromise and will make
help you feel more comfortable cruising on the highway.
If their is a supercharger in your future I wouldn't go with too
low of a gear 3.73's or 3.90's at most.
 
Plus you have a DOHC 4.6, and they really dont mind revving at all. Even though I would really have to think on 4.10's for my 2v GT I would not hesitate to put them in any 4v car with that extra 1k rpm to play with, not to mention the 4v's top end charge.
 
Ok. So I researched, and found a RPM calculator that said at 75 in 5th, with 4.10's I should be at about 2450, and at 85 I should be at about 2750. Does this sound right ? Sorry for asking this redundent question, but I dont have wads of $$$ so I like to only do mods once. I wouldnt want to get 4.10's and find out they were too much. Or get 3.73's and not feel much of a difference. Even though the car is not my daily driver, I still want to get out on the open road and cruise. And I do want to do a little bit of drag strip duty, but mostly just be able to terrorize cars on the streets. For now I just want to be able to take LS1's till i get my blower. Then it's C5 Z06's, terminators, and STI's ETC..

I have 4.10's and 75mph is slightly under 3K, not 2400. Adding gears will not allow you to terrorize C5 Z06's either. The only difference you will see is that 1st gear becomes useless and you end up going through the traps in the very top of 4th instead of the bottom (with the same ET).
 
I put 4.10s on a GT/auto and my comfortable cruising speed is now around 60 mph. At 70-75, the engine is near screaming. Letting off the pedal does a serious engine brake. At 55-60, it goes into coast mode if I let off a little.

Are you saying 4.10s are to much for an auto? Its to much of a toss up for me. 3.73s, 3.90s, 4.10s. With the mods I have now I lose traction with the stock 3.23s.
 
I had 3.73's in my '03 GT,5 speed equipped,and after awhile i got board.Didn't really notice anything.Maybe i am just to picky.So i went to 4 10's and wished i spent the money on gear swap once,not twice :nonono: !
I highway drive aswell for a 6 hour drive (one way) twice a year,plus car shows out of town,and i tell you,i get between 500 to 600 km's out of her on that 6 hour trip,and that depends on MY FOOT! :nono:
4.10's aren't as bad as some think :shrug: .I was there once too.
What most need to remember is,and this was posted in an old Muscle Mustangs issue....
3.27 in a 5.0 = 3.55 in a 4.6
3.55 in a 5.0 = 3.73 in a 4.6
3.73 in a 5.0 = 4.10 in a 4.6
4.10 in a 5.0 = 4.30 in a 4.6
The 4.6 needs gear to gain the little torque it has to compare to the little 5.0's torque.The seat out of the pants thing :nice: .
I know if everyone here had a 5.0,they would go with 3.73's in a heart beat,or some have had 5.0's and have done 3.73's.So why shouldn't the 4.6 be any different.If the 4.10 in the 4.6 equals to the 3.73 in the 5.0,wouldn't you go 4.10's???!!!
And you know what,the 5.0 with 3.73's still feels waaaay more torqier then a 4.6 with 4.10's Weird eh. :shrug:
My bro has 3.73's in his '89 GT (stock except for exhaust),so it's easy for me to compare.
 
Are you saying 4.10s are to much for an auto? Its to much of a toss up for me. 3.73s, 3.90s, 4.10s. With the mods I have now I lose traction with the stock 3.23s.
I would not put 4.10s in an auto *if you spend a lot of time on the freeway going 75+ and very little city driving*. If you live in the city where most freeway speeds are around 60 and you do mostly city driving, you'll love 'em.
 
I know this question has probably been asked hundreds of times on here, but I need a solid answer so I had to ask again. I really want to swap out my factory gears in my 03 mach 1 to 4.10's. The probem is I like to cruise at 75-80 mph on the highway. Basically my question is where exactly will my rpm's be cruising at 75 mph. I have been getting mixed answers ranging from 2500-3500. If its 2500-2800 I think I could take that, but 3500 is a bit high to me. My rear tires are 295/35/18. Plus I plan on doing a procharger in the next year or so. Am I better off going with 3.73's, or is that just a waste of money going from 3.55 to 3.73's? I wish i could ride in someones car that has 4.10's, then I would know exactly how its gonna be. Unfortunately none of my freinds own stangs. I know this sounds like a newbie question, but Im not a newbie. I just have never done gears in any of my stangs yet... Thanx

I have been using 4.10's in my DD '03 Mach 1 for the past three years, and wouldn't have any less. RPM on the freeway don't hit 3000 until 90 mph in fifth gear. We also use 4.10's in my wife's DD '04 V6 automatic, and it doesn't hit 3,000 rpm until around 78 mph while highway cruising. Gas mileage has not suffered significantly in either vehicle.