Max recommended tire size for 5-speed 4.0 Rubicon without re-gearing?

YonderNorthwest said:
Jeep geared Rubicon to 4.10 to accommodate 31" tires. Jeep geared non-Rubicon Dana 44'd TJs to 3.73 to accommodate 30" tires.

I have 3.73 gears with 31" tires and a 5 speed tranny. I can't start from a stop in 2nd as easily as I could with 30" tires, and 5th gear doesn't like hills. Does this sound like your experience on 32" tires? If so, I wouldn't recommend jumping up to 33s without a regear. If 32s aren't giving you trouble in 5th on hills, I'd say go for 33s.

Don't buy rough country lift kit. Do some reading on this forum and you'll find some MUCH better performing builds for not much more money.

Welcome to the forum. Prepare to empty every pocket.
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The post I'm referring to in the tj resource thred uses new springs with a 2" lift with the suggestion of new rancho 5000x shock's. Sorry, I'm not techy enough to link it. You should be able to find in the tj resource thred though.
 
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I have a 2” OME lift, BL, MML and run 33s with zero vibrations…it honestly rides better than my daily driver. I have factory control arms and adjustable front and rear track bars.

04855DD2-9C84-4087-B344-7FB9662BB832.jpeg
 
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riosouza said:
As for now, I might go for a 2.5" lift suspension.
Is there anything decent and affordable?
Should I buy the complete kit like Rough Country, or is better buy the springs and shocks separated from different brands?
Do I need to replace the motor mount?
Sorry for all the questions, but I want make it right.
Thanks!
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Rough Country and Skyjacker are at the bottom of the quality/ride barrel. No need to replace the motor mounts. Check out Zone's suspension lifts, they get a lot of good reviews. I don't know of many 2.5" lifts, include 2" heights in your search too.
 
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YonderNorthwest said:
Jeep geared Rubicon to 4.10 to accommodate 31" tires. Jeep geared non-Rubicon Dana 44'd TJs to 3.73 to accommodate 30" tires.
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Jeep geared 5 speed manual, 6 speed manual and 4 speed automatic to same 4.10 gear ratio with 31 inch tires. It is not because this ratio is optimal for all 3, it is because it is cheap to have the same axles everywhere.
It the right gear for 5 speed, slightly too much for 6 speed (could do with 3.73 as well), and significantly undergeared for automatic.
I will give you another example. In Israel, Israeli military military wanted TJs from local factory (there was one building Jeeps there). After R&D, they came up 6 speed manual (same as in 2005-2006 TJs) with 4.10 ratio, 32 inch tires, SYE from factory with NP231 and rear Dana 44. They deployed these in masses (i drove one myself back then, at least many hundreds deployed and used from desert to mountains), and it was running great for flats and mountains/hills. It was also slightly heavier, because of metal hardtop and 4 door design with longer frame.
If you look at 42RLE, the 4 speed that I have in my TJ today, it needs 4.56 gears to run the 31 inch tires that TJR has. I have 4.56 gears and I run 32 inch, and it is not the proper gear. I need to have 31 inch in order to be in the right RPM band.
 
riosouza said:
The "budget boost" are nothing more than spacers to the springs, mostly for aesthetics, making the ride more stiff and less plushy.
Without replacing the shocks it will not add any travel to your suspension, and they now extra compressed springs will extend your shocks too hard causing premature damage to its internal components. I've been there done that. Thanks for the suggestion though.
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The springs aren't anymore compressed with spacers than without. They alone will not affect ride. The bit about needing to replace shocks is exactly correct though.
 
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If I were you, I'd do the aforementioned - A 1.25" BL and 1" suspension lift is very good for a 32" build. I have a 4" spring lift on 35's now, bought with this lift but had skinny 33's like in my avatar. I just wanted to say that my next mod will likely be lowering my JEEP some and going back down to 32s or 33s. That may likely be way down the road since my gears and 35s are only about 3 months old.
You lose a little bit of fun factor as you get higher. It may look cool but it comes at the price of feeling a little top heavy.
 
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Zone used to make a nice Combo lift for right around $500. It was a 2.5" suspension lift, and 1.25" body lift, or a 3" and 1" and could be paired with some cheap shocks that were reported to ride really decent. From what I remember Zone is the budget brand of BDS suspension, and the lifts were designed to clear 33's or 35's without needing drive train mods or a t-case drop.

Edit: Found these:

https://www.extremeterrain.com/zone...WlGIPNR4qGsUoRxjQ8waAkSfEALw_wcB&gclsrc=aw.ds

https://www.extremeterrain.com/zone...QA4bX9KBbGrlic34aXgaAmZCEALw_wcB&gclsrc=aw.ds

https://www.quadratec.com/p/3-suspe...W1Q2xKgZcjQLnb3nNHyDyshGTenWTMrIaAmuzEALw_wcB
 
For 2" I would the bb with new shocks and 32" tires. I had this on my jeep for about a yr with no issues. Added a body lift for a bit more fender clearance. Then bit the bullet on a 4" lift.
Only reason I mention that is because alot of people that go 2" seem to want more not long after so a bb fits the bill and wheels just as good as 2" coils.
 
I run 33x10.50 BFG KO2s with 4.11s / 5 speed and I am pretty happy with the power. I think a lot of that has to do with going with a 10.50 wide tire rather than a 12.50. I ran 31x10.50 BFG KM3s prior to the 33s on the 4.11s and I think the power is about the same. Probably due to the KO2 being a bit lighter in the 33x10.50.
 
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Dick_Slade said:
I run 33x10.50 BFG KO2s with 4.11s / 5 speed and I am pretty happy with the power. I think a lot of that has to do with going with a 10.50 wide tire rather than a 12.50. I ran 31x10.50 BFG KM3s prior too on the 4.11s and I think the power is about the same. Probably due to the KO2 being a bit lighter in the 33x10.50.
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My Jeep actually came with KO2s on 33x10.50 with 3.73s. Always just felt like the usual sluggish Jeep to me. I have recently went to 4.88s on 35x12.50s. Feels about the same as the 3.73s with 33x10.50 to me..
 
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FJQue said:
My Jeep actually came with KO2s on 33x10.50 with 3.73s. Always just felt like the usual sluggish Jeep to me. I have recently went to 4.88s on 35x12.50s. Feels about the same as the 3.73s with 33x10.50 to me..
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I love how the 33x10.50s perform both on and offroad. Really happy with the slight weight saving as well over the 12.50s. Biggest reason I went with the 10.50s was I did not want to regear to 4.56s but I could not be happier with how well they perform.
 
Dick_Slade said:
I love how the 33x10.50s perform both on and offroad. Really happy with the slight weight saving as well over the 12.50s. Biggest reason I went with the 10.50s was I did not want to regear to 4.56s but I could not be happier with how well they perform.
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I'll probably drop down to 33's again when I lower this thing & get it race track ready.
 
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