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Discussion Starter #1 (Edited)
Im lookin at purchasing 35" mt/r tires.. i will be purchasing a 2.5 lift along with the tires.. my question is will the stock 6 spd gears be able to handle the tire size? I read in another thread discount said that the tires should be available mid to late march.
 

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Your profile says you have a Sport, but doesn't indicate what gears you have. Sports come standard with 3.21s, but have an option for 3.73s. The 3.73s on a 6-spd should be fine. You'll probably lose 6th gear around town, but it'll still be useful on the highway. With 3.21s you'll be struggling a little and lose 6th gear completely. You'll probably be wanting to re-gear sooner.

On the trails, if you crawl, you'll want to re-gear with either.

Get the 35s and you can always re-gear later.
 

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5.13 is perfect!!!
 

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4.56 would make a nice highway/road gear, 4.88 would be ideal in my opinion, help the crawl some off-road...but if there is ANY chance you want to go 37s or bigger, definitely consider 5.13s
 

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35s with 2.5 inch RK running 3.73 starting tomorrow (stock) 5.13s on the way
 

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I remember looking to regear my TJ that I had to get new carriers also?! Are these needed on the JKs also? I'd assume a D30 is a D30 right (looking for a stronger axle actually)... and of course the 44 in the rear? I can't even find carriers to swap gears.
 

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What year is your Jeep? The 3.8 V6 will require 4.10's as the tallest gearset that'll be happy with the 6-speed. If you have a 2012 with the 3.6 V6, then I can't speak with any personal experience.
 

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513, 6 speed on 35's. no regrets. runs at about 2800ish rpm doing 65.

also, i would recomment gussets and sleeves. i have them. HUGE improvement over stock
 

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35s with 2.5 inch RK running 3.73 starting tomorrow (stock) 5.13s on the way

Hey- how is this setup running for you? Is it unbearable on the highway at speeds of 60 or 70.
Bump on this, I would love to kow also! This is the same exact set up I'm looking at (minus the 5.13s for now)
 

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I am running 35" MTR/Ks with 4.10 gears (Rubi 6 speed) and a 3.5" lift for a year and had 35" Cooper MTs on it prior to that with 4.10s. It's doable but would be better regeared. If you have an automatic like my previous JK with 35s and 4.10s (Rubi), it's a DOG on hills unless you disengage the electronic O/D!!! At least with a stick you can downshift to 5th and keep on cruising.
 

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I've got 35s running a 3.5" lift with 3.73s right now. Most of my time is spent on the road since it is my DD, but I'm a weekend wheeler. I want to go up and was looking at 4.56, but I seem to be reading that 4.88s are ideal? I wanted to know how this affects highway driving? Anybody else have this issue? Also, I only have the 4-speed auto, so I think that changes things.

Also, would it be easier to re-gear, or just swap out for a new axle(s) with the specified gear ratio?
 

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Running 35" BFG MT's on OEM wheels with 1.5" spacers on an '08 4 door Rubi with full soft top/half doors an the auto trans.

It wasn't an interstate hill champ with the stock tires, but with a downshift out of OD, it was fine. This V-6 loves to rev, so it has no problems doing so wth the 35's.

The 35's are only on the JK when we go wheeling.Otherwise it wears a set of the 17" Goodyear all-seasons. So changing gears is not an option for us.

Overall, yeah, they slow it down a little, but not a significant amount. I think 4.88's would be too much gear for 35's.

Sorry if this post wanders. I had a few customers come in while trying to post it. :)

cell post
 

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I just put in 4.56
 

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I recently changed to 4.88's from stock 3.21's on my 3.6 manual with 35's. I was debating between 4.56 & 4.88 and decided to go to 4.88 because I tow a lot. The tires measure actual 34". I am happy I went 4.88. 2700 rpm at 70 is fine. It seemed a little high at first, but I am used to it now. I can drive 80 no problem, which I don't do very often. The power really makes a difference though. I never have to downshift going up hills on the highway anymore and I can pretty much roll around town at any speed in 4th.
 

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Great insight on gear ratios in this thread. MY 2011 JK standard 6 speed transmission with 3:21 gears ratio and I have (265[30"] 70 17) AT tires on right now and just added a 2.5 inch lift.

From what I gather if I wanted to go up to a 35" tire I should regear to at least 4.10.

MY 30" tires run about 2000 rpm at 70 mph, a 35" tire as the chart reads that my rpm would drop to 1800 rpm or maybe lower?

I don't do much highway driving so it may be okay? but would gas mileage go down?

I'm around 16 mpg avg. right now.

So as I hear a 33" from a tire store, may be the tallest I should go with to keep mpg the same and rpm's the same and not have to regear? Although I see here in the Forum 35" to 37" are the go to tire size.

Hopefully I can get some feedback from longtime members here or merchants.

Thank you in advance.
 
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