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I have an '08 X, where can I find on the vehicle what the gear ratio is? I believe it may have 3:21s. I am running 315 MTZs, so what would a more appropriate ratio be? Finally, how difficult is the process of changing out the gears? Thanks in advance for any help you can give me!:confused:
 

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If you have a manual you can have 3.21 or 3.73. The 3.73 was an upgrade option. If you have a automatic tranny then you have a 3.73.

I have 4.88's in mine and think they work great with my 35's
 

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It's a manual. Did you do your own work?
 

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If you log on to the Jeep website you can request a "build sheet" with your V.I.N. They will e-mail you the build sheet within a day.

I have a 2010 JKU automatic with 35's. I went with 5.13 gears. Changing the gears takes some tech experience. My advise would be to take it to a trustworthy shop who does gears.
 

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What were the improvements with the gear change? More power? Pick up from a stop? Pick up at speeds? Mileage?
 

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Re-gear doesn’t give you more power as it has nothing to do with the engine. It does make the driveability 100% better. Lowere RPM, better MPG, less doggy at accel, so on…A 3.8L with manual would benefit from 4.88 gears for 35’s.

-Dan
 

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If you log on to the Jeep website you can request a "build sheet" with your V.I.N. They will e-mail you the build sheet within a day.


I have a 2010 JKU automatic with 35's. I went with 5.13 gears. Changing the gears takes some tech experience. My advise would be to take it to a trustworthy shop who does gears.
Will do. Thanks!
 

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I have a 08 auto with 35"s but it's also my daily driver. Would 5.33 gear ratio be too much for toll road speeds?
 

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I went from an '08 with 3.21 to 4.11. The difference was dramatic, its like a totally different vehicle. RPM's are definitely higher than before but now I can actually use 6th gear on the highway.
 

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I went from an '08 with 3.21 to 4.11. The difference was dramatic, its like a totally different vehicle. RPM's are definitely higher than before but now I can actually use 6th gear on the highway.
How much higher? Auto or manual? I have an 08 with 3.21 gears (manual) on 33's. Considering either 4.10's or 4.56's. I do a mix of highway and stop n go street driving.
 

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How much higher? Auto or manual? I have an 08 with 3.21 gears (manual) on 33's. Considering either 4.10's or 4.56's. I do a mix of highway and stop n go street driving.
It's a manual. When I drive home today I will take down some RPM numbers at different speeds in all the gears so that you can compare it to yours. I am very happy with the 4.11 gearing and don't think I would go any higher unless I was considering putting on 37"s. Shifting is much different now, I find that i cruise around in a higher gear than I used to and 6th gear isn't completely useless anymore, I love it.
 

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I have a 08 auto with 35"s but it's also my daily driver. Would 5.33 gear ratio be too much for toll road speeds?
There's no 5.33. Do you mean 5.13 or 5.38?

3.8L, automatic, 35s, 4 door and I was still disappointed when I switched from 4.10s to 5.38s. Streetability didn't improve as much as I hoped, felt like I just got back my overdrive and 4:10 OD off drove better than 5.38 OD on around town.
 

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There's no 5.33. Do you mean 5.13 or 5.38?

3.8L, automatic, 35s, 4 door and I was still disappointed when I switched from 4.10s to 5.38s. Streetability didn't improve as much as I hoped, felt like I just got back my overdrive and 4:10 OD off drove better than 5.38 OD on around town.
Oh yea ha that's what I meant. With the above stats would I notice a difference from 3.71 to 4.10 or 5.13?
 

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How much higher? Auto or manual? I have an 08 with 3.21 gears (manual) on 33's. Considering either 4.10's or 4.56's. I do a mix of highway and stop n go street driving.
Here are the numbers I got last night comparing engine speed to road speed with 4.10 gearing. You should be able to use this to compare to your Jeep with 3.21 axle ratio.
 

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