4.88 or 5.13 with 6 speed manual and 38's for a daily driver
03-20-2017, 05:29 AM
#11
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Yes I use first gear, I like my clutch to last as long as possible lol
All kidding aside with 5.13 and 37's my Rubicon feels very close to how it did stock with 4.10 gears (meaning the engine, throttle, and driveability of it.).
*Edit: No surprise I just checked the gear chart and at 70 it's only turning 200 revs more than a stock MT Rubicon would (~2530 vs 2740.). Yours on 38's would be even closer at like 2670 revs.
All kidding aside with 5.13 and 37's my Rubicon feels very close to how it did stock with 4.10 gears (meaning the engine, throttle, and driveability of it.).
*Edit: No surprise I just checked the gear chart and at 70 it's only turning 200 revs more than a stock MT Rubicon would (~2530 vs 2740.). Yours on 38's would be even closer at like 2670 revs.
03-20-2017, 01:41 PM
#12
Former Vendor
5.13s are the way to go with that setup. The 3.8 is more impacted by load and heat than RPMs, they seem to be perfectly happy winding their way down the freeway. Besides, with a 38" tire on a 3.8 JK there isn't much to be done for fuel economy anyway.
If you're going to thrash your Jeeps on the rocks, you might consider a 4.88 for strength, but if you're a mindful driver a 5.13 will be fine.
Either way, it'll work.
If you're going to thrash your Jeeps on the rocks, you might consider a 4.88 for strength, but if you're a mindful driver a 5.13 will be fine.
Either way, it'll work.
03-20-2017, 04:08 PM
#13
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Which gears for a 3.6 6-speed on 37's? I got PR60's coming with 5.13's, went a little lower because it's starting to get heavy. I still daily drive it so I was conflicted between those and 4.88's
03-20-2017, 05:48 PM
#14
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I went 4.88 with that setup and it is perfect. Honestly the 5 13's may be a little better around town, but may get annoying on the interstate. 4 low with the Rubi transfer case is awesome.
03-21-2017, 02:04 AM
#15
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Plenty of power on the highway? Mine is a '13 rubicon so I'm not worried about off road either way. Thinking of changing order before they build axles
03-21-2017, 04:18 AM
#16
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I'm building a set of Rubi axles with 4.88 to run 37's, should be installing here a couple weeks. By the chart 4.88 will put you in the middle of the green band for 37's. My Cooper STT Pro run closer to a 36 though, so it may have me in the top end of the blue band. I tend to run on the highway a lot for wheeling trips, so that is the main concern. My last Jeep was geared way too low, 4.56 on 33's in a YJ. Its road manners were not very nice.
03-22-2017, 03:03 AM
#18
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Hey all,
Have my re-gear appointment setup for next week and I'm confused as to which I should choose. I would love some real life input because charts don't factor weight of the vehicle
I would consider my JK fairly heavy with all steel armor and a winch, plus the bigger wheels and tires ( mods are in sig ) but this is a daily driver that needs to see 75-80 comfortably on the highway since I'm on the highway a lot.
I feel 4.88 is the better highway choice but 5.13 would be better for getting around town . not sure ? any input is appreciated
This is costly and I don't want to regret.
Have my re-gear appointment setup for next week and I'm confused as to which I should choose. I would love some real life input because charts don't factor weight of the vehicle
I would consider my JK fairly heavy with all steel armor and a winch, plus the bigger wheels and tires ( mods are in sig ) but this is a daily driver that needs to see 75-80 comfortably on the highway since I'm on the highway a lot.
I feel 4.88 is the better highway choice but 5.13 would be better for getting around town . not sure ? any input is appreciated
This is costly and I don't want to regret.
you need more than 5.38 
