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I know gears have been beat to death, but....

Radar

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After reading and reading on this site it sounds like i should be able to get away with 315's on my JT sport (no S, No Max Tow, not even power windows). I have the Manual transmission, not sure of the gears in it currently but it's stock. I'm leaning towards 4.56's and more then likely will go that direction. question is how much power will I lose jumping to the 315 tires. undriveable on the interstate at 70-80mph bad or just expect to get the RPMs up a little more each gear a little longer.

not planning on offroading this one that's what the TJ is for.

mixed city/interstate driving in Florida so no hills

how bad of a hit without gears to MPG, currently at 22MPG

also what gears do I have?
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bleda2002

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With a manual go higher, on the jl jeeps offers 4.88s for 315s with a manual. If you regear you won't notice a big power loss as 315s aren't huge anyways.
 

JT1

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After reading and reading on this site it sounds like i should be able to get away with 315's on my JT sport (no S, No Max Tow, not even power windows). I have the Manual transmission, not sure of the gears in it currently but it's stock. I'm leaning towards 4.56's and more then likely will go that direction. question is how much power will I lose jumping to the 315 tires. undriveable on the interstate at 70-80mph bad or just expect to get the RPMs up a little more each gear a little longer.

not planning on offroading this one that's what the TJ is for.

mixed city/interstate driving in Florida so no hills

how bad of a hit without gears to MPG, currently at 22MPG

also what gears do I have?
You have 3.73s now. Expect 6th to be unusable until you are going 80+. 5th should be usable on the highway at 70~75. Ist gear is going to be tall, and reverse will stink.

If you spend a ton of time on the interstates or turnpikes at 75+ go 4.56. If you don't, 4.88s. If you were at elevation or near mountains, I would shift to go straight to 4.88s. I have 37s and 5.13s and there are times where I'd like another gear (7th)
 
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Radar

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and axles in this jeep I assume are d44 m210 front and m220 rear?

I'm running Yukon's in the TJ but it's offroad only and never had any issues with them but from reading I'm getting mix feeling here. is it spicer or go home, or other brands?

skipped a few years of jeep stuff(98 TJ), trying to catch up on the gladiator
 

Minty JL

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I'm going 4.88
 

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My truck is in the shop as I type, having 5.13 gears installed. I'm on 37s and the 3.73 was arguably 'fine' in town. Would hate to see mountains. Went 5.13s for the 37s and the extra weight it's put on lately with the armor. The shop I went to said Dana or Revolution, but won't play with Yukon.
 

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your window sticker will tell you what axles and gears you have
 
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Radar

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next part of the equation, tazer (or equivalent). on reading it seems pretty important on the automatics, other then recaling the speedometer is it that important in the MT?
 

JT1

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next part of the equation, tazer (or equivalent). on reading it seems pretty important on the automatics, other then recaling the speedometer is it that important in the MT?
You can use anything you'd like to set tire size and gear ratio. You will have to do the 6th gear relearn if you want to use cruise.

Set the tire size and gear ratio on the jeep. Then unplug the batteries for 15 minutes. Then get it in 6th gear and drive it varying the throttle for a few minutes to get the jeep to recognize the new parameters.

Automatics don't have to do this, but us manual guys do.
 

exfil offroad

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My truck is in the shop as I type, having 5.13 gears installed. I'm on 37s and the 3.73 was arguably 'fine' in town. Would hate to see mountains. Went 5.13s for the 37s and the extra weight it's put on lately with the armor. The shop I went to said Dana or Revolution, but won't play with Yukon.
your gonna love the 5.13 it makes the truck pick up like its weightless.
 

exfil offroad

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After reading and reading on this site it sounds like i should be able to get away with 315's on my JT sport (no S, No Max Tow, not even power windows). I have the Manual transmission, not sure of the gears in it currently but it's stock. I'm leaning towards 4.56's and more then likely will go that direction. question is how much power will I lose jumping to the 315 tires. undriveable on the interstate at 70-80mph bad or just expect to get the RPMs up a little more each gear a little longer.

not planning on offroading this one that's what the TJ is for.

mixed city/interstate driving in Florida so no hills

how bad of a hit without gears to MPG, currently at 22MPG

also what gears do I have?
Keep in mind you can get away with it, but your transmission is going to work way harder with the lower gearing than it will with higher gearing. The wear and tear will catch up in my opinion. That said I had 315's on for a short period before re gearing a auto trans. The pick up was slow and the truck didnt want to go above 6th gear most of the time. I went to 5.13 have much heavier components on it and a smart cap evo a and the truck accelerates almost like a sedan and i hit 8th gear in city. IMO its worth dropping the 2 gs for new gears.
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