33's with 4.88 gear ratio? thoughts?
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33's with 4.88 gear ratio? thoughts?
Soon I will be regearing my JK. I have 33's right now and eventually I will go up to 35's but that is as big as I will get. I have the 3.8L engine and I will be keeping my D30/D44 setup, so I didn't want to go any lower than a 4.88 gear ration in the D30. Any thoughts as to how 4.88 gears will do with 33's, especially on the highway? Offroad, will I really notice that much of a difference from my 3.73 setup now?
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From: Michigan
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From: Billings, MT
If you are going to eventually upgrade to 35s, do 5.13s with a 07-11 automatic.
If you think that would bee too deep, know that your highway rpms with 5.13s, automatic and 33s will be about the same as a 6 speed Rubicon with stock Rubicon tires.
4.88s with 33s will turn lower rpms at highway speeds, with lower power/performance than a stock Rubi 6 speed.
Lower rpms = more frequent transmission downshifting for automatics = worse mpg.
If you think that would bee too deep, know that your highway rpms with 5.13s, automatic and 33s will be about the same as a 6 speed Rubicon with stock Rubicon tires.
4.88s with 33s will turn lower rpms at highway speeds, with lower power/performance than a stock Rubi 6 speed.
Lower rpms = more frequent transmission downshifting for automatics = worse mpg.
Thread Starter
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Joined: Jan 2012
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From: Michigan
If you are going to eventually upgrade to 35s, do 5.13s with a 07-11 automatic.
If you think that would bee too deep, know that your highway rpms with 5.13s, automatic and 33s will be about the same as a 6 speed Rubicon with stock Rubicon tires.
4.88s with 33s will turn lower rpms at highway speeds, with lower power/performance than a stock Rubi 6 speed.
Lower rpms = more frequent transmission downshifting for automatics = worse mpg.
If you think that would bee too deep, know that your highway rpms with 5.13s, automatic and 33s will be about the same as a 6 speed Rubicon with stock Rubicon tires.
4.88s with 33s will turn lower rpms at highway speeds, with lower power/performance than a stock Rubi 6 speed.
Lower rpms = more frequent transmission downshifting for automatics = worse mpg.
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From: Billings, MT
About what?
For an 07-11 automatic, you want 5.13s for 33s and 5.38s for 35s or larger. Since no one makes 5.38s for Dana 30s anymore, 5.13s are the lowest you can go for non-Rubicons.
For those that think that this is too low, they need to understand that 5.13s and 33s run about the same highway rpm as a stock 6 speed Rubicon--not too high at all.
For an 07-11 automatic, you want 5.13s for 33s and 5.38s for 35s or larger. Since no one makes 5.38s for Dana 30s anymore, 5.13s are the lowest you can go for non-Rubicons.
For those that think that this is too low, they need to understand that 5.13s and 33s run about the same highway rpm as a stock 6 speed Rubicon--not too high at all.
Last edited by planman; Oct 14, 2013 at 08:42 AM.
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Thread Starter
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Joined: Jan 2012
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From: Michigan
About what?
For an 07-11 automatic, you want 5.13s for 33s and 5.38s for 35s or larger. Since no one makes 5.38s for Dana 30s anymore, 5.13s are the lowest you can go for non-Rubicons.
For those that think that this is too low, they need to understand that 5.13s and 33s run about the same highway rpm as a stock 6 speed Rubicon--not too high at all.
For an 07-11 automatic, you want 5.13s for 33s and 5.38s for 35s or larger. Since no one makes 5.38s for Dana 30s anymore, 5.13s are the lowest you can go for non-Rubicons.
For those that think that this is too low, they need to understand that 5.13s and 33s run about the same highway rpm as a stock 6 speed Rubicon--not too high at all.
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From: Austin <--> Colorado Springs
Open the FAQ's stickied to the top of this modified area, click into the drivetrain section, and start plugging some numbers into the charts. You will find that 6th gear on manuals and 4th gear (OD) on auto's have different ratios. So for the same size tire, autos and manuals have different gearing needs.
For a 3.8 manual on 35's - 4.56 and 4.88 are popular.
For a 3.8 auto on 35's - 4.88, 5.13 and 5.38 are popular. (need a front d44 for 5.38's)
For a 3.8 manual on 35's - 4.56 and 4.88 are popular.
For a 3.8 auto on 35's - 4.88, 5.13 and 5.38 are popular. (need a front d44 for 5.38's)
Last edited by nthinuf; Oct 14, 2013 at 10:06 AM.
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From: Billings, MT
3rd gear in the automatic has the same ratio as 5th gear on the manual.