O/D off equivalent to Re-gear
#11
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I just always imagined re gearing and it holding 4th.
#12
#13
JK Enthusiast
go to this website Gear Ratio Calculator
in 1 column enter 4.10's, in the other enter 5.13's and compare the 2 side by side.
I used 42RLE for transmission, NVG241or for t-case and 33.75" tire for 35's.
With 5.13's, in 3rd gear, 60mph you're going to be sitting at ~3050rpms, 70mph will be at ~3600rpms.
With 4.10's, in 3rd gear, 60mph you're going to be sitting at ~2450rpms, 70mph will be at ~2850rpms.
You say it is dropping into 2nd gear now... sooo...
With 4.10's, in 2rd gear, 60mph you're going to be sitting at ~3850rpms, 70mph will be at ~4500rpms.
Since under load the 3.8 is going to work best between 3500-4500rpm (TQ peak)...
I'm betting that you will go up moderate/typical grades in 3rd at 70mph with 5.13's(3600rpm) that currently with with 4.10's will be asking for 2nd gear to do 60mph(3850rpms). I'm also betting it will go up lots of slight grades in 4th at 2400rpm where currently it's looking for 3rd and 2850rpms.
Good luck.
in 1 column enter 4.10's, in the other enter 5.13's and compare the 2 side by side.
I used 42RLE for transmission, NVG241or for t-case and 33.75" tire for 35's.
With 5.13's, in 3rd gear, 60mph you're going to be sitting at ~3050rpms, 70mph will be at ~3600rpms.
With 4.10's, in 3rd gear, 60mph you're going to be sitting at ~2450rpms, 70mph will be at ~2850rpms.
You say it is dropping into 2nd gear now... sooo...
With 4.10's, in 2rd gear, 60mph you're going to be sitting at ~3850rpms, 70mph will be at ~4500rpms.
Since under load the 3.8 is going to work best between 3500-4500rpm (TQ peak)...
I'm betting that you will go up moderate/typical grades in 3rd at 70mph with 5.13's(3600rpm) that currently with with 4.10's will be asking for 2nd gear to do 60mph(3850rpms). I'm also betting it will go up lots of slight grades in 4th at 2400rpm where currently it's looking for 3rd and 2850rpms.
Good luck.
#14
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go to this website Gear Ratio Calculator in 1 column enter 4.10's, in the other enter 5.13's and compare the 2 side by side. I used 42RLE for transmission, NVG241or for t-case and 33.75" tire for 35's. With 5.13's, in 3rd gear, 60mph you're going to be sitting at ~3050rpms, 70mph will be at ~3600rpms. With 4.10's, in 3rd gear, 60mph you're going to be sitting at ~2450rpms, 70mph will be at ~2850rpms. You say it is dropping into 2nd gear now... sooo... With 4.10's, in 2rd gear, 60mph you're going to be sitting at ~3850rpms, 70mph will be at ~4500rpms. Since under load the 3.8 is going to work best between 3500-4500rpm (TQ peak)... I'm betting that you will go up moderate/typical grades in 3rd at 70mph with 5.13's(3600rpm) that currently with with 4.10's will be asking for 2nd gear to do 60mph(3850rpms). I'm also betting it will go up lots of slight grades in 4th at 2400rpm where currently it's looking for 3rd and 2850rpms. Good luck.
I just need more HP!!!!
#15
JK Jedi
any time you go up a steep hill your transmission is going to shift into a lower gear. With your current set up I would just leave it but if you go to an actual 35"+ tire a re-gear should be considered. Not having proper gears puts stress on the entire drivetrain including the driveshafts.
#16
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any time you go up a steep hill your transmission is going to shift into a lower gear. With your current set up I would just leave it but if you go to an actual 35"+ tire a re-gear should be considered. Not having proper gears puts stress on the entire drivetrain including the driveshafts.
#19
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Yeah. It's just a dog. Before I put anymore money into the 2dr I'm going to wait to see what the jl is like. If I don't like that then a 4 door jk it will be.
Either way it'll be a 6 speed
Either way it'll be a 6 speed
#20
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3.73's and O.D off was ok. But, ended up regearing to 5.13's, because I wanted Trutrac's front and rear. If, it is power you want, then drop coin on a V8 and not another dog. Glad, I do not live where there are big mountains!
Last edited by GunDude; 04-18-2017 at 08:00 AM.