5.13 or 5.38
#1
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5.13 or 5.38
Ok since everyone seems to be asking gear questions here's mine.
I hav an 08 rubicon umlimited auto and am about to install a 3.5" RE superflex lift. The original plan was to run 35's but I am certian 37's will end up on it eventually. I was planning on installing 5.13's but was wondering if anyone has actually thrown in 5.38's and could post their pros & cons.
So the question is.
Should I stick with the 5.13's or have enough people installed 5.38's to prove they are a reliable option for a JK?
Thanks
I hav an 08 rubicon umlimited auto and am about to install a 3.5" RE superflex lift. The original plan was to run 35's but I am certian 37's will end up on it eventually. I was planning on installing 5.13's but was wondering if anyone has actually thrown in 5.38's and could post their pros & cons.
So the question is.
Should I stick with the 5.13's or have enough people installed 5.38's to prove they are a reliable option for a JK?
Thanks
#3
JK Super Freak
I've got 5.13s and 40" tires. In fact the other JKs on here running large tires most all run 5.13 gears. The 5.38s seem to be seperated from the 5.13s by only a few hundred RPMs, so the difference isn't that much. Plus I heard that the extremely small pinion gear on the 5.38 is just waiting to get chewed up from running large tires (much like the rest of our Jeep).
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I've got 5.13s and 40" tires. In fact the other JKs on here running large tires most all run 5.13 gears. The 5.38s seem to be seperated from the 5.13s by only a few hundred RPMs, so the difference isn't that much. Plus I heard that the extremely small pinion gear on the 5.38 is just waiting to get chewed up from running large tires (much like the rest of our Jeep).
I cant imagine what a Dog the JK is with 40's.... Is it your DD?
Your right, the crawl ratio is really low, In moab I found myself in 3rd or 4th gear between the rocks
#6
JK Super Freak
Oh heck no! I drive a car day to day (38 mile commute) plus I don't think my clients would appreciate climbing on all fours trying to get into it while wearing a business suit
I don't think I would ever recomend 40's for a DD since depending on your commute distance, you'll eat up alot of expensive tire, burn through alot of gas (<$2/gal ain't bad right now though) and have little power off the line. Push it down to 37's and now we may be talking. It is surprising though how much power was restored when I added the Gibson exhaust, intake and TBS. I definitely didn't buy the Jeep for it's on-road performance
I don't think I would ever recomend 40's for a DD since depending on your commute distance, you'll eat up alot of expensive tire, burn through alot of gas (<$2/gal ain't bad right now though) and have little power off the line. Push it down to 37's and now we may be talking. It is surprising though how much power was restored when I added the Gibson exhaust, intake and TBS. I definitely didn't buy the Jeep for it's on-road performance
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#8
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Thanks for everyones responce. I had settled on 5.13's until 5.38's started showing up again. Looks like I should stick to the original plan and throw the 5.13's in.
Thanks
Thanks
#9
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I've got 5.13s and 40" tires. In fact the other JKs on here running large tires most all run 5.13 gears. The 5.38s seem to be seperated from the 5.13s by only a few hundred RPMs, so the difference isn't that much. Plus I heard that the extremely small pinion gear on the 5.38 is just waiting to get chewed up from running large tires (much like the rest of our Jeep).
Also interesting you mentioned the relatively small rpm difference between 5.38s and 5.13s as there are a lot of people that would act if their nuts just got smashed by a hammer if you were to suggest the same from 5.13s to 4.88s which have about the same 5% difference.
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I have a 6spd. Would that change any of your opinions?
I have stock tires on my rubicon and in Moab I found that I wanted a slightly lower first gear. In my TJ, with a STRAIGHT 6 (I miss that motor), I was able to idle more without feathering the throttle up the steap stuff. I was thinking 5.13s with 35s would give me that little extra but 5.13s with 37s may not be enough.
Who makes 5.38? I do not think superior or dana has this option.