What gears are good for 38" tires and Ecodiesel?

[rcr1340]

I am going to order a JLUR with the diesel. I see plenty of people running 3.6l and 2.0l with factory 4.11 and rolling 37's or 38's. I think with the extra torque of the diesel the factory 3.73's will be just fine. What has people done with diesels and gearing?

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[Compression-Ignition]

If you're contemplating it I would regear. It drives fine with the 3.73's and 37/13.5r17 Toyo MT's, but I would not make the claim it is ideal. I'd go 4.56's at least for 38's.

 

[JLURD]

What is your intended use? Rock crawling, overland, desert, woods, highway?

 

[rcr1340]

I was actually wondering if anyone with a diesel has had to regear and what size tires are they running. I have looked thru the few diesel builds and noone has regeared

 

[Compression-Ignition]

To follow up on the re gear question. Has anyone dropped gears in a diesel running 37's. I'm sure the diesel can roll on the stock 3.73 not problem given the power, but to get it as close to stock as possible you'll need a little more than 4.10. 4.33 isnt an option anymore which would be ideal, and I feel going 4.56 would just be way overkill for regular driving. I'm about to order new ultimate dana 44's and need to make the decision. I had planned on ordering with 4.10, but wanted to see if anyone has gone beyond at this point to get their opinion? I tow a trailer with a pair of touring Harleys. So I'll be up another 2300lbs behind me in full tow.

And a reply to the above.

I re geared to 4:56 going from 37s to 40s. I drove the jeep about a week on 37s and the 4:56 combo. Imo 4:56 is perfect for the 37s. The jeep felt stock with that gear ratio. Acceleration from a dead stop to highway speeds was great. Makes me wish I would have gone 4:88 for the 40s.

^^^ Diesel owner

I originally was annoyed that we couldn't order our diesels with 4.10's. 4.10's would have been more livable after any tire upgrade. I agree 4.30's would have been a nice compromise, but I couldn't find that option, which left 4.56's......

Page 6 here https://www.jlwranglerforums.com/forum/threads/diesel-lift-kit.47537/page-6

 

[TomahawkChop]

Makes me wonder why Jeep wouldn't let you opt for the 4.10's with the Eco-Diesel... Apart of me thinks one reason could be because they don't think their axle could handle the extra torque compared to the gas engines.

 

[Compression-Ignition]

Makes me wonder why Jeep wouldn't let you opt for the 4.10's with the Eco-Diesel... Apart of me thinks one reason could be because they don't think their axle could handle the extra torque compared to the gas engines.

I think it was purely so they could claim the higher mpg numbers. No doubt it would have dropped their averages a little with 4.10's vs 3.73's.

Would have been great for those that knew they were going to upgrade to 37's.

 

[JINO]

Sorry for resurrection...

I'm looking to regear.
I think 4.11 would be best for 37x13.5x17
I'm having a little trouble looking.
Some sites say 'gas only'. Are the diff housing different for gas and diesel?

It seems Yukon and currie are most popular?

I do mostly mountain terrain and desert, not too much rock crawling (anymore).

The 3.73 feels fine with the diesel, but many have said 4.11 is closest to stock feel. My 37s are 70 lbs, but going for sst pro (13.5) next, I believe 85 lbs.

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