4.56 or 4.88?

WildCatguy

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I need some feedback of those who have 4.56 or 4.88, how do you like them? Pros/cons?

I have MT Sport with 35’s and trying to decide what gears to get.

Any advice is much appreciated.
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roaniecowpony

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Mostly dirt or highway?
 

Arterius2

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I need some feedback of those who have 4.56 or 4.88, how do you like them? Pros/cons?

I have MT Sport with 35’s and trying to decide what gears to get.

Any advice is much appreciated.
If mostly highway, I would say 4.56 for MT for optimal power band. If you had an auto I would have said 4.88
Since your highest gear is 0.72 vs 0.67 on the auto. And you don’t get the power loss due to torque converter.
4.88 would be a little overkill for 35s.
 
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D60

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You lose the infinite gear reduction of a torque converter so 4.88 no question.

Worst case you lose 0.1% mileage over 4.56 - who cares
 

UKCATS

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I vote 4.88. I ran and 35’s and 4.88’s on manual transmission JK’s, and on my auto trans JL and it was perfect.
 

Xtremetj

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Without a doubt... 4:88s.
 

roaniecowpony

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Use this calculator to run some various speeds with the two candidate ratios and you can get rpm at a selected speed.
http://advanced-ev.com/Calculators/TireSize/

For example: with a 34.5" tire (many "35 inch" tires are actually shorter),
4.56 gears, .72 high gear = 3.28 final drive ratio, which calculates to 75 mph = 2396 rpm
4.88 gears, .72 high gear = 3.51 final drive ratio, which calculates to 75 mph = 2564 rpm
 

Roky

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I need some feedback of those who have 4.56 or 4.88, how do you like them? Pros/cons?

I have MT Sport with 35’s and trying to decide what gears to get.

Any advice is much appreciated.
If it was me I’d do 4.88, because if you ever decide to go 37s, it will handle it better...:)
 

Jeepjunkie

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You can’t go wrong either way, but here is my experience.
I have 4.56s on a 6 speed and 33s. I think it will be perfect for 35s when I go up in tire size. Right now I have a lot of power and never need to downshift over 65mph. I hit 72 mph at 2500 revs. I’d like to hit 75 mph at 2500 revs, which I’ll do with 34-35” tires. I still get 19+ mpg. With 4.88s and my current tires I’d hit 2700 revs at 72 mph, which is revving faster than I’d like (personal preference).
 
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WildCatguy

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Use this calculator to run some various speeds with the two candidate ratios and you can get rpm at a selected speed.
http://advanced-ev.com/Calculators/TireSize/

For example: with a 34.5" tire (many "35 inch" tires are actually shorter),
4.56 gears, .72 high gear = 3.28 final drive ratio, which calculates to 75 mph = 2396 rpm
4.88 gears, .72 high gear = 3.51 final drive ratio, which calculates to 75 mph = 2564 rpm

Thank you!
 

D60

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The calculators essentially assume operation in a vacuum and zero-gravity.

Bigger tires - and usually a lift - you're sitting higher, catching more wind, you want a little deeper gear to compensate.

Similarly a larger tire is heavier, it takes more to get going and keep going. None of this is accounted for in the basic math of revs per mile, kilometer, whatever
 

The Viking

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The calculators essentially assume operation in a vacuum and zero-gravity.

Bigger tires - and usually a lift - you're sitting higher, catching more wind, you want a little deeper gear to compensate.

Similarly a larger tire is heavier, it takes more to get going and keep going. None of this is accounted for in the basic math of revs per mile, kilometer, whatever
It is really mass, not gravity that you are fighting on level terrain.
 
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