Getting 37's need hep choosing gears

2me's JK

2me's JK

New member
Hi!
I'm getting 37" Nitto Trail Grapplers on my 2014 Wrangler Unlimited.
I think they will actually measure around 35" .

What gear ratio would you recommend?
This is my daily driver and will be wheeling two-three times a month.
I'm thinking about:
4.56
4.88
5.13 seems like it would be too much and a rather high RPM (2,862 rpm if they do actually measure 35") when on the highway.

What do you recommend?

Thanks!




JT
 
There are several threads already on gearing but this should help you. You also need to mention what transmission you have.

ImageUploadedByWAYALIFE1404954161.271040.jpg
 
2me's JK said:
Hi!
I'm getting 37" Nitto Trail Grapplers on my 2014 Wrangler Unlimited.
I think they will actually measure around 35" .
Click to expand...

I think they measure 36"

I have 5:13's and it is only about 200 more rpm at freeway speed

I haven't really worked out 4 low that much yet but with some light playing around the crawl is pretty nice with this gear.
 
I posted the gearing chart on another thread like this from my computer. I'm not at home now but if you Google "gearing chart JK" and look in the image results you'll find the chart for our engines.

2014 JKUR
 
An advertised 37" tire will have an actual measurement that is closer to 35". Having said that, when talking about gears, you should be looking at the advertised size and NOT the actual. You only want to look at actual size when calibrating your speedometer.

Having said that, with a 3.6L motor like you have, 4.88's will get you running back at stock performance. 5.13's is what I have and would recommend as it'll give you a bit more power without running too high on the RPM's on the highway. 5.38's will be even better but, won't be as friendly on the highway.
 
I run 5.13's and 37's and love it. I do live in the mountains though. If I did alot of freeway driving which I never do I would go 4.88's

Sent from my SAMSUNG-SGH-I537 using WAYALIFE mobile app
 
wayoflife said:
An advertised 37" tire will have an actual measurement that is closer to 35". Having said that, when talking about gears, you should be looking at the advertised size and NOT the actual. You only want to look at actual size when calibrating your speedometer.

Having said that, with a 3.6L motor like you have, 4.88's will get you running back at stock performance. 5.13's is what I have and would recommend as it'll give you a bit more power without running too high on the RPM's on the highway. 5.38's will be even better but, won't be as friendly on the highway.
Click to expand...

Thank you, I did not realize the difference between gearing and speedometer.
So it will only 132 RPM difference between 4.88 & 5.13
Are you running 37's or 40's with the 5.13?

Thanks again!


JT
 
2me's JK said:
Thank you, I did not realize the difference between gearing and speedometer.
So it will only 132 RPM difference between 4.88 & 5.13
Are you running 37's or 40's with the 5.13?

Thanks again!


JT
Click to expand...

On my 2012, I am running 37's with 5.13's. I do a ton of driving all over the country and find that it's still a great setup.
 
I did 5.13 on mine about 6000 miles ago. Have done several road trips an the rubicon and really like the gearing.


- Jason
 
I'm having my 5.13's done in 2 weeks for my 2014 with 37's and auto. What speeds are you all traveling at on the interstates? Some of our speed limits are 75mph so I've heard from local shops that 5.13's will get too hot. Thoughts?
 
I have 4.88s on 37 nitto trail grapplers and love them, that being said i have a standard, i also am able to stay in 6th going up normal hills. Wen it comes to going up in the mnt i have to play both 5th and 6th! but def between 5.13s and 4.88s. (maybe 5.13s if you have a 44 in front) my speed is 75 to 80 about 2900/3100 rpms
 
Last edited:
On the 5.13 gears, how many teeth are actually engaged?
I remember one shop saying the 5.13 only had a few teeth engaged and more likely to snap a tooth than 4.88.
Any truth to that?

Thanks again, you all have been very helpful.
Very much appreciated!


JT
 
2me's JK said:
On the 5.13 gears, how many teeth are actually engaged?
I remember one shop saying the 5.13 only had a few teeth engaged and more likely to snap a tooth than 4.88.
Any truth to that?

Thanks again, you all have been very helpful.
Very much appreciated!


JT
Click to expand...

For a D30 that is the case. D44 has a bigger ring gear so it does fine.
 
wayoflife said:
On my 2012, I am running 37's with 5.13's. I do a ton of driving all over the country and find that it's still a great setup.
Click to expand...

Is there any compelling circumstance or reason that you would ever recommend 4.88 on 37's?

Thank you, I thought I saw 40's on one of your videos.

Thanks again for all of your advice!



JT
 
You must log in or register to reply here.
Top Bottom