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intentsrig

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Yea. With 37's
Looks like about 2400. So it was less for sure with 35’s despite a previous post of mine haha. I had never looked at 70 with 35’s. Starts to eat the fuel up fast anything over 70.

I can still pull on the freeway even in 6th. It’ll jump up from 65-75 no prob
 

rcr1340

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Thanks for the info. I'm gathering facts to decide on what gear I go with. Only want to regear once. Way to expensive to do multiple times.
 

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Thanks for the info. I'm gathering facts to decide on what gear I go with. Only want to regear once. Way to expensive to do multiple times.
I have a manual rubi with 37's and can't decide on 4.88's or 513's. I mostly drive on back roads but will be on the interstate at 80mph occasionally. Not sure if the 5.13 will be over 3000 rpm at 80mph. I have used the calculators but have also seen post that say the actual rpms are higher than the calculators show. Any help would be appreciated.
 

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rcr1340

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I have a manual rubi with 37's and can't decide on 4.88's or 513's. I mostly drive on back roads but will be on the interstate at 80mph occasionally. Not sure if the 5.13 will be over 3000 rpm at 80mph. I have used the calculators but have also seen post that say the actual rpms are higher than the calculators show. Any help would be appreciated.
I have been crunching numbers ever since the transmission gear ratios on the JL was released. I very much understand drive ratio/crawl ratio and overdrive factors. I have asked alot of questions and read every thread I can find. These are the numbers I have came up with. For the manual transmission, I would gear 4.56 for 37's, 4.88's for 38-39s, 5.13 for 40's and 5.38 for 42's. For the automatic, 4.56 for 35's, 4.88's or 37-38, 5.13 for 39-40's, and 5.38 for 42's. These tire sizes are for true sizes not advertised sizes. Some tires are closer to true size than others. The manual trans has a lower first gear than the automatic(5.13 vs 4.71) but the automatic has a deeper over drive than the manual(.72 vs .68). Part of the reasons I have came to this reference. This is for JL only. Every transmission needs different gearing. These numbers are not perfect but I believe from all my research they will be great ratios for on and off road. Also I am not saying all axles can handle any of these combinations.
 
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I have a manual rubi with 37's and can't decide on 4.88's or 513's. I mostly drive on back roads but will be on the interstate at 80mph occasionally. Not sure if the 5.13 will be over 3000 rpm at 80mph. I have used the calculators but have also seen post that say the actual rpms are higher than the calculators show. Any help would be appreciated.
I love the 5.13’s. You should think about how it will drive when loaded down with camping gear as well.

I found out that I still needed 4th gear with 37’s/ camping gear/ 1 passenger and dog. Only on two very steep grades, once I was in the mountains I could use 5th uphill mainly and 6th occasionally. 4.88’s just wouldn’t cut it.
 
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Never added this. Just a little homemade shelf. Used aluminum C channel front and back to add strength.

It’s been painted black since

FCA2FC35-4751-4E7F-96D9-E3CB47CE83C9.jpeg


9D2A3C63-8AFD-44B5-AB86-1BBCC4FFABEA.jpeg


886D72CB-DCE7-419C-812C-29741FCC93E8.jpeg
 

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Looks like about 2400. So it was less for sure with 35’s despite a previous post of mine haha. I had never looked at 70 with 35’s. Starts to eat the fuel up fast anything over 70.

I can still pull on the freeway even in 6th. It’ll jump up from 65-75 no prob
Great looking build...Running at 2400 rpm's at 70 mph seems a little high in the rpm's for folks that want to maximize fuel economy. With a 6 speed and 35's with 4.10 gearing, I'm cruising at 2100 rpm at 70 and get 19-20 mpg. I'm curious about going with 4.88 gearing with the 37's. Your rpm's would be even higher running 35's and 5.13.

In regards to the e lockers that come with the stock rubi d44 axles, they arent made by Eaton on the jl. I talked with Eaton and FCA switched vendors away from them and went with a Japanese company for the jlur e lockers.
 

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Great looking build...Running at 2400 rpm's at 70 mph seems a little high in the rpm's for folks that want to maximize fuel economy. With a 6 speed and 35's with 4.10 gearing, I'm cruising at 2100 rpm at 70 and get 19-20 mpg. I'm curious about going with 4.88 gearing with the 37's. Your rpm's would be even higher running 35's and 5.13.

In regards to the e lockers that come with the stock rubi d44 axles, they arent made by Eaton on the jl. I talked with Eaton and FCA switched vendors away from them and went with a Japanese company for the jlur e lockers.
Interesting, I’m fairly certain the engineers at dana spicer told me it was an Eaton, at least for the UD. I think I’ll call on Monday.
 

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Interesting, I’m fairly certain the engineers at dana spicer told me it was an Eaton, at least for the UD. I think I’ll call on Monday.
Let me know if you hear something different...I talked with Eaton, Spicer and Advantec and it was consistent. Also, they said the rear d44 with limited slip that is an upgrade on the jlus is 1.5" narrower than the jlur d44 axles with e locker. Did you find this to be true when you measured for your front super 44?
 

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Any update on a bracket for the fenders? I’m still wanting to do this on my sport and I haven’t found anything available yet.
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