Rubicon - 5.13 or 5.38's for Re-Gear?

ravencr said:
Shifting down constantly to 3rd gear at 79mph is terrible...running 500rpm or more constantly is not big deal.

Chris
Click to expand...
It's going to be a bigger issue when you overheat on mountain grades revving the shit out of your motor like I did. You can take my opinion for what it's worth, I've actually had the tire size/gear set so I can confidently say it was shit. You sound like you have your mind made up anyway, so this post is pretty irrelevant.

Sent from my ONEPLUS A3000 using WAYALIFE mobile app
 
I'm not following you. Are you saying it's better for it to shift down to 3rd and 4th gear and rev the crap out of it every time it comes to a hill, or it's worse to have it constantly be running at a higher RPM? I'm not following...my mind isn't made up.

Chris
 
ravencr said:
I'm not following you. Are you saying it's better for it to shift down to 3rd and 4th gear and rev the crap out of it every time it comes to a hill, or it's worse to have it constantly be running at a higher RPM? I'm not following...my mind isn't made up.

Chris
Click to expand...

No, I'm saying you should consider 4:88's if this is your daily driver.
I'm not saying what you currently have is better by any means, but it doesn't make sense to go to one extreme to avoid another.
Your original thought was "I'm constantly shifting, let's go with the most gear possible"
ravencr said:
I'm leaning towards 5.38's
Click to expand...
That doesn't make any sense though, now you're revving too high in the gear you're supposed to be in as you would be with 5:13's.
If 37's are a month or two out, then sure, it might be tolerable, any longer and I (personally) would reconsider your decision.
Just an FYI, I still have to downshift with 5:13's and 37s on big hills otherwise it bogs out.
 
Maybe he didn't calibrate the speedo. I wouldn't take my jeep over 80. Even crossing Texas with an 80mph speed limit, she's so much happier at 73.....
 
I am firmly in the 4.88 camp with 37’s. Even at that I don’t want to run over 65. I can’t imagine wanting to run long distance at higher RPM’s, just so it does not downshift - to what - higher RPM’s? I have driven it across country 5 times and tried my best to stay off interstates and on as many back roads/dirt roads/trails as possible, just because I have a Jeep.

To those that want to run a JK over 80, it’s your Jeep, do as you please but you might consider trading up to a JL. That one is designed for it. My JK is not.


Sent from my iPhone using WAYALIFE mobile app
 
When people say they wouldn't drive fast in a jeep I laugh. I tend to drive fast in whatever I am driving. I have zero concerns doing 90+ with my 37s 5.13s and a 3.8. I catch myself in that range on a regular basis.


Sent from my iPhone using WAYALIFE mobile app
 
QuicksilverJK said:
When people say they wouldn't drive fast in a jeep I laugh. I tend to drive fast in whatever I am driving. I have zero concerns doing 90+ with my 37s 5.13s and a 3.8. I catch myself in that range on a regular basis.


Sent from my iPhone using WAYALIFE mobile app
Click to expand...
Same. 🤣
QuicksilverJK said:
That being said my old TJ wanted to run me off the road if I hit 65 . I guess it's all in how well you're front end is dialed in.


Sent from my iPhone using WAYALIFE mobile app
Click to expand...
☝️ This for sure. I laugh when I hear others talk about how poorly lifted Jeeps handle... I just think to myself "you're doin' it wrong" as I fly by 'em. 😎

--
Build Thread - Adventures of Fiona - https://wayalife.com/showthread.php?t=47407
 
All of my M38’s and M38A1’s came with 5.13’s. Going that route when warranty expires in 8 months. I’ll be looking for advice from you folks concerning tire size then.


Sent from my iPhone using WAYALIFE mobile app
 
BaddestCross said:
Same. 🤣

☝️ This for sure. I laugh when I hear others talk about how poorly lifted Jeeps handle... I just think to myself "you're doin' it wrong" as I fly by 'em. [emoji41]

--
Build Thread - Adventures of Fiona - https://wayalife.com/showthread.php?t=47407
Click to expand...

If you have a cheap ass lift, the Jeep will handle poorly. If you address caster, roll center, and bump steer, as most of the better (and more expensive) kits do, it will handle fine.
 
‘11 jkru 3.8 engine, manny tranny. Went to 5.13’s and lovin it! Currently running 35’s, will go to 37’s next time.
 
Last edited:
When I went to Evo to get a re-gear I asked for 5:13's. They talked me into 5:38 because I have the 3.8 auto. I'm glad they did! At 70 with 37's it sits very nicely in the powerband.43384.jpg43383.jpg43362.jpg
 
jjlong said:
When I went to Evo to get a re-gear I asked for 5:13's. They talked me into 5:38 because I have the 3.8 auto. I'm glad they did! At 70 with 37's it sits very nicely in the powerband.]
Click to expand...

5.38s are the best ratio for that setup, except that the pinion gear is tiny and vulnerable to breakage, assuming you’re on 44s. If you’re just cruising on pavement, it’ll probably hold up ok.
 
You must log in or register to reply here.
Top Bottom