Preliminary 2012 Pentastar Gear Chart (beta)
11-25-2011, 03:07 AM
#21
JK Newbie
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The 2012 Rubicons with 4.10's are in good shape for 35's
If my Sport had 4.10's I'd leave it alone...
I am impressed at how well mine pulls with 3.73's and 35's !....auto
As of today I'm installing 4.56's and ARB's
No doubt 4.56's will pull 37's nicely if I ever decide to go bigger..
Gene
If my Sport had 4.10's I'd leave it alone...
I am impressed at how well mine pulls with 3.73's and 35's !....auto
As of today I'm installing 4.56's and ARB's
No doubt 4.56's will pull 37's nicely if I ever decide to go bigger..
Gene
11-25-2011, 07:48 AM
#22
JK Enthusiast
Every time I read about the 2012's and the Pentastar with the new auto I get a little more depressed.... I guess I'll just have to go buy my JKU something else to make me feel better. 
11-25-2011, 07:57 AM
#23
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Originally Posted by Friday2322
Every time I read about the 2012's and the Pentastar with the new auto I get a little more depressed.... I guess I'll just have to go buy my JKU something else to make me feel better.
11-25-2011, 08:06 AM
#24
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The charts for the 3.8L are in the FAQ, but here's a copy of them. The charts for the 3.8L and the Pentastar are virtually the same for the manual transmission as Chrysler dropped some juice out of the OD gear. The automatic is where the huge gains are and personally it's enough for me to forego a manual transmission this time around.
11-26-2011, 06:47 AM
#25
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The 2012 Rubicons with 4.10's are in good shape for 35's
If my Sport had 4.10's I'd leave it alone...
I am impressed at how well mine pulls with 3.73's and 35's !....auto
As of today I'm installing 4.56's and ARB's
No doubt 4.56's will pull 37's nicely if I ever decide to go bigger..
Gene
If my Sport had 4.10's I'd leave it alone...
I am impressed at how well mine pulls with 3.73's and 35's !....auto
As of today I'm installing 4.56's and ARB's
No doubt 4.56's will pull 37's nicely if I ever decide to go bigger..
Gene
01-05-2012, 08:50 PM
#26
JK Newbie
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chart question
Good to get some validation of the chart data. I'm definitely stoked about the options and believe someone with 4.10s and 35s will reveal just how far you can push things without seriously degrading economy. 4.10s, OD off is the same as 4.88s at cruise speeds, so your findings with 4.56s being in between will definitely help define the chart data moving forward.
01-06-2012, 07:47 AM
#27
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I am just curious, and i do not have any validation because i have not yet put bigger tires on my 12, but according to this chart i could get away with numerically lower gears on say a 33" tire with an auto trans than with a manual....that just seems funny, even if they are closely geared because dont you get more hp loss through an auto than with a manual, has any one out there put 33's on their 12 with a manual with their stock gears?
01-06-2012, 08:05 AM
#28
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I had 4.56 gears installed in my 2012 Sahara unlimited manual. I have to say that it is the perfect setup with 35's. Couldn't be happier with the power. Anything more would be too much.
