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Discussion Starter · #1 ·
What complications will I have with stock gearing when pushing these? Just loss in fuel economy and top speed?
 

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Greater stress on the engine and tranny when you don't regear. Harder time in braking also if you don't upgrade that either.
 

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What complications will I have with stock gearing when pushing these? Just loss in fuel economy and top speed?
A few things we need to know to answer. What year is your Jeep? 2012+ has 70 more horsepower so the 35's it seems most people can tolerate with stock gears. The second more important question is which stock gears you have, 3.21 or 3.73 or even 4.10's if it's a Rubi? 3.21's with 35's isn't recommended though some people do it. 3.73's seem to be tolerable to most people. Looks like you may be from Florida which helps, since you won't have many elevation changes.
 

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Discussion Starter · #4 ·
A few things we need to know to answer. What year is your Jeep? 2012+ has 70 more horsepower so the 35's it seems most people can tolerate with stock gears. The second more important question is which stock gears you have, 3.21 or 3.73 or even 4.10's if it's a Rubi? 3.21's with 35's isn't recommended though some people do it. 3.73's seem to be tolerable to most people. Looks like you may be from Florida which helps, since you won't have many elevation changes.
2011 2dr jk automatic. I believe it has 3.73 gears correct?
 

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2011 2dr jk automatic. I believe it has 3.73 gears correct?
I believe it would have come standard with 3.21 but the buyer could have opted for the 3.73's. Not sure how you could tell without the window sticker or seeing if a dealer can run the VIN to see the options to be honest. Maybe someone else will chime in with more info.
 

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You can check the rear differential for a metal tag that says the gear ratio.
 

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Just put the right gears in your Jeep. The consensus best gear ratio is 5.13. That is a big difference from 3.73. The performance will be lousy and you will completely loose the use of top gears on inclines. If the Jeep drove like that when you bought, it is highly doubtful you have still purchased it.
 

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As FloridaRunner said you can check for a tag on the diff...if you don't have one (like mine) you can request a build sheet. That could take longer than you're willing to wait so a quick sure fire way would be to see how many revolutions your drive shaft makes for 1 (one) rev of your tire, that's your ratio. Make a mark on the shaft with a paint pen or sharpie (something of the sort) and hopefully with some help roll SLOWLY and count the revolutions of the drive shaft. Just short of 3.5 revolutions=3.21 gears...just over 3.5 but not quite 4=3.73. If you have 3.21's you'll prob want to regear fairly soon. If you have 3.73's...35's can be tolerated esp if you're on flat land. You will notice a slight drop in performance and fuel economy, which you could get back by regearing down the road. It really comes down to personal preference
 

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...and just an fyi, the general "consensus" would be that 5.13's would be a little too extreme for you to go to just for 35's. Pending what you use your jeep for, 4.56 is a happy medium that most would recommend. 5.13's are 37's and up territory with serious off roading in mind
 

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I agree with DuneSahara and just adding my .02 cents here not that I have 35's or a regear done to mine, but from what I've read on the forum here the sweet spot for 35's is 4.56 I've asked a similar question about this. 5.13 people say is good for a lot of off roading but if it's a daily driver you may something less aggressive.
 

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2011 was still the 3.8 engine. Optimal gearing for 35s on that engine for a street rig are 5.13 or 5.38 - and up for more trail crawling ability. Which will be way small in a D30 housing.

To give you an idea of the advantage of the newer 3.6, 4.10 and 4.56 would be acceptable street gearing.
 

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Discussion Starter · #12 ·
I just wasn't looking to drop $1000 on a regear right now. I live in Florida so the terrain is mainly flat. Does anyone run 35"s currently on stocking fearing that can give input?
 

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I just wasn't looking to drop $1000 on a regear right now. I live in Florida so the terrain is mainly flat. Does anyone run 35"s currently on stocking fearing that can give input?
It isn't about whether someone can tolerate it or will it run. Being improperly geared regardless of your terrain stresses the engine and transmission. So you will spend $1k plus on tires but not gears? Wait until you can do them at the same time.
 

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I just wasn't looking to drop $1000 on a regear right now. I live in Florida so the terrain is mainly flat. Does anyone run 35"s currently on stocking fearing that can give input?
You really should find out what your specific "stock gearing" is in this situation. 3.21 with the 3.8L will not be enjoyable. 3.73 will probably be tolerable, and 4.10 I wouldn't ever worry about changing unless I just had money to blow.
 
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