Gear Ratio Chart for JL Wrangler?

The Great Grape Ape

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The gears felt tall even in the 4:10 axle ratio JLUR I test drove. With the 3:44ish ratios in the Sport, I might not be using 6th gear very much.
Yeah, that’s what Dan jokingly said when he first went out with the JLUR so of course 3.45 will exacerbate that, but that’s not new, having a JK with the NSG MT @0.84 and 3.21 that was already the case (many people proudly exclaimed they just used the first 5 anyways), and the 0.74 Aisin with 3.45 is pretty close by with only 8% diff, versus the AT’s 15% so it would be expected, but still necessary to provide some headroom for mods, options, uses and road conditions.





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That One Guy

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Yeah, that’s what Dan jokingly said when he first went out with the JLUR so of course 3.45 will exacerbate that, but that’s not new, having a JK with the NSG MT @0.84 and 3.21 that was already the case (many people proudly exclaimed they just used the first 5 anyways), and the 0.74 Aisin with 3.45 is pretty close by with only 8% diff, versus the AT’s 15% so it would be expected, but still necessary to provide some headroom for mods, options, uses and road conditions.
Ah, thanks for the information! I didn't know what the 6th ratio was in the old NSG. Sounds like the 0.81 in fifth should be a pretty good cruising gear if I just wanna use that. I like these things being geared a bit short, so that they can hold their own on the road. I'd like that engine to be turning a good 2500rpm at 80 or so, considering I don't really go 80 in a Wrangler.

But yeah, when I threw the JLUR in 6th at 70mph at it went to a flat 2000rpm, I was a bit surprised.

I also kinda wanted to get away with running 33's without a regear, which probably won't be as ideal here as it would've been with the old optional 3.73's. Frankly if they announced a 2019 JL Willy's I'd wait.
 

The Great Grape Ape

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I also kinda wanted to get away with running 33's without a regear, which probably won't be as ideal here as it would've been with the old optional 3.73's. Frankly if they announced a 2019 JL Willy's I'd wait.
It’ll be interesting to see if they bring out a 3.73 option for an eventual SE like a Willys, originally in the JL(U) 3.73 was only slated for the Rubi and then all the EcoDiesel options, but it never materialized for the Rubi, and I don’t know if they’d break out the option beyond the diesel for something else if their focus remains primarily MPG, but I sure would prefer the balance myself as I would be stock or optional 33 max also (depends on what mine has as options or what cheap take-offs I can get at the time).
 

damage618

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So i have a question, I have a 2018 wrangler unlimited sahara JL with 3:45 gears if i had them changed to 4:56 would that also change the ration of all of my gears? I have a M/T. because right now 6 gear is there for show only, because lets be honest it only makes power @ or above 2100 rpms, so 5th gear is good all the way to 75+ mph, I tested my cruise control @75mph 5 gear I was getting 23mpg. and 6th gear 20 mpg. (according the the computer on my dash and it has been very accurate after testing it through 5 tanks of gas and comparing it to the calculator.) so the big question is this. will i gain ALOT of power by going to 4:56 gears and not lose ALOT of mpg. and will it change the ratio of gears 1-6 and maybe convert it to a single overdrive?
 

TJMJLWRANGLER

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Hey All,

I see there are a number of different calculators out there.
That said they are often difficult to follow and usually give way to much information. So I did my own if anybody else is considering doing a swap and wants to explore more.
On this one, you can play with the RPM and look at the speeds for a couple of options compared to current / stock at the same time.
So, conclusion between 4.88's and 5.13's. At 77 MPH, it's really only a difference of 100 RPM. Changes from 2300 for the 4.88's to 2400 for the 5.13 at 77MPH with an auto in 8th gear.
Or that 100 rpm in 8th gear is 77mph for the 4.88s and 74 for the 5.13's.
That said, the stock jl loved 7th gear doing 74 before at 2300, so if I can have that with the 5.13's in 8th's gear, it seems perfect. At this point, I'm driving on sport 3.45 gears (yuk) with 37's and it drives like it wants to live in 5th and drinks its weight in gas (9-10mpg).
I might go for a test spin now and lock it at 2400 vs 2300 rpm and see if there is any noticeable noise, responsive difference just to be sure.

I've attached the calc file if anyone want's a play with it too. Change the inputs in the red to your desired settings.
diff gear calc ss.JPG
 

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Arterius2

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Go here and plug in the JL numbers, it works.
TRANSFER CASE: MP3022 SELEC-TRAC
  • Available: Optional – Sahara
  • Type: Full-time
  • Operating Modes: 2WD High; 4WD High; Neutral; 4WD Low
  • Low Range Ratio: 2.72:1
Why does the internal spec sheet for MP3022 Selec-Trac show 4.0:1 low range? Euro Spec? Thought the spec sheet was for NA version.
http://chryslermedia.iconicweb.com/mediasite/specs/2018_JP_Wrangler_SPqqqbu093eu5bvdt6d69jkbljjo.pdf
https://www.extremeterrain.com/everything-about-the-jeep-jl-wrangler.html
222.JPG


2221.JPG
 
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Bushwick18

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