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Right way and costs to do 37s on a jtr

wanderer

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Toying with the idea of 37s. But thinking it’s gonna get pricey. So I’ll need tires wheels (can you use the stock wheels?). And re gear? To what 488 or 5 something? Then a tazer to recalibrate your speedo. And the lift? 2.5 ? 3.5?
So what does it cost? Is it worth it? This is my daily driver mainly an overlander what are your pros and cons and what did you settle on?
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You need at least 2.5” lift and the right bump stops for 37” tires. The bump stops are important if you plan to flex your suspension. With the sway bar disconnected.

You need aftermarket wheels with proper offset/backspacing to help the wider tires clear the frame. You can also use stock wheels and spacers, depending on local DOT laws.

Gears however are a matter of preference and based largely on how and where you drive: off-road, on local roads or highway, live in hilly terrain, do you tow, baby or mash the skinny pedal, etc.
 

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You can put 37’s on stock JTR wheels with no lift as long as you are not expecting full articulation for rock crawling or driving over smaller cars at the mall.
 

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I was going to say this as well, but OP did ask what the “Right way” was.
 

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I will second that no off road and you can just put the 37s right on but any off road and definitely with a sway bar disconnected and you will likely rip your fender flares off. The “right way” (meaning time feel and perform like stock driving) is 2.5” or more lift, front and rear track bars, proper bump stops, shock extensions or longer shocks, some stiffening of the steering (maybe a synergy front steering system), front lower control arms, optional rear upper(or lower) control arms, calibration of the computer for the tire size (and gears if you do that too), optional but highly recommended 4.88 gears. The gears could be skipped if you are ok with losing 8th and don’t tow.
 

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wanderer

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Right way means no cheap shortcuts. Stock or better performance. None of the abilities of the stock jtr are comprised. Only enhanced. Big question is. Cost
Tires 1500
Gearing 2000? That’s a wild guess
Lift kit 1500
new shocks 4 @ 250. 1000
Wheels 1000 5 @200
Labor 1200. That’s a guess tool
Taser mini 225
total 8425 ? Seems high

what is a good budget?

Where can you save on this without really sacrificing any goals

Could you the stock wheel. And just have more sidewall bulge?
 
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wanderer

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Along a similar line of thought. If you went with 35s could you add a wheel spacer to minimize or eliminate rubbing at full flex off road with stock rims an a 12.50 x 35 tire? With 35s where does it actually rub?
 
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Toying with the idea of 37s. But thinking it’s gonna get pricey. So I’ll need tires wheels (can you use the stock wheels?). And re gear? To what 488 or 5 something? Then a tazer to recalibrate your speedo. And the lift? 2.5 ? 3.5?
So what does it cost? Is it worth it? This is my daily driver mainly an overlander what are your pros and cons and what did you settle on?
You have a Rubicon, so you can get by with the bare-minimum for now. But you will eventually need to re-gear to 4.88's for proper utilization of the 37" tires. Reprogramming works wonders, but it will only get you so far. You will always need to re-gear the vehicle to regain from performance loss. So, keep in mind, that will need to be done in the future. The 4:1 transfer case, and 4.10 gears of the Rubicon really help to negate that for a little while, and helps your offroad performance until you can afford the re-gearing cost (around $2,000-$2,500 depending on your location and what type of shop you go to).

Here is my list for the doing it right, but on a budget...

Evo Manufacturing 2.5" Enforcer Stage II Plus suspension lift w/ shock bracket to reuse your stock Rubicon Fox shocks ($1,600).

Aftermarket wheels (size of your choice, plus brand, plus finish, will determine price (plan for $1,200, you can probably find some you like for less). Plus add around $100 for a new set of TPMS sensors, so you don't have to pay the tire shop to dismantle your factory tires & wheels.

Tires... 37x12.50 or 37x13.50 tires will run you $300+ each, mostly ranging around the $400 each price tag. I recommend the Kumho Road Venture MT KL71's that I am running, they're budget-friendly at only $298 each @Discount Tire , and they're great tires.

And then finally labor for everything... That will vary from shop to shop, and location to location. I would say $500-$750 to install the lift and do a proper 4-wheel alignment afterwards. Mount and balance & TPMS install for 4 wheels and 37" tires should run you around $100-$150.

Tazer JL Mini will run you $329, and you can install it yourself...Super simple.
 
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brianinca

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You don't have to do anything to run 35's on a Rubicon. The OEM wheels are fine as well, the whole 8.5" rim thing is not a thing. There is no rubbing or contact even under full flex with the swaybar disconnected.

You will have higher ground pressure even when you air down, though. Compared to 35's, the 37's will give you a bigger contact patch and still give you more ground clearance.

Along a similar line of thought. If you went with 35s could you add a wheel spacer to minimize or eliminate rubbing at full flex off road with stock rims an a 12.50 x 35 tire? With 35s where does it actually rub?
 

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You have a Rubicon, so you can get by with the bare-minimum for now. But you will eventually need to re-gear to 4.88's for proper utilization of the 37" tires. Reprogramming works wonders, but it will only get you so far. You will always need to re-gear the vehicle to retain performance loss. So, keep in mind, that will need to be done in the future. The 4:1 transfer case, and 4.10 gears of the Rubicon really help to negate that for a little while, and helps your offroad performance until you can afford the re-gearing cost (around $2,000-$2,500 depending on your location and what type of shop you go to).

Here is my list for the doing it right, but on a budget...

Evo Manufacturing 2.5" Enforcer Stage II Plus suspension lift w/ shock bracket to reuse your stock Rubicon Fox shocks ($1,600).

Aftermarket wheels (size of your choice, plus brand, plus finish, will determine price (plan for $1,200, you can probably find some you like for less). Plus add around $100 for a new set of TPMS sensors, so you don't have to pay the tire shop to dismantle your factory tires & wheels.

Tires... 37x12.50 or 37x13.50 tires will run you $300+ each, mostly ranging around the $400 each price tag. I recommend the Kumho Road Venture MT KL71's that I am running, they're budget-friendly at only $298 each @Discount Tire , and they're great tires.

And then finally labor for everything... That will vary from shop to shop, and location to location. I would say $500-$750 to install the lift and do a proper 4-wheel alignment afterwards. Mount and balance & TPMS install for 4 wheels and 37" tires should run you around $100-$150.

Tazer JL Mini will run you $329, and you can install it yourself...Super simple.
This is almost my build so I agree with the doing it right but on a budget. I am running a EVO 2.5" Enforcer stage 2 (resulted in over 3" of lift) on my Rubicon (includes front and rear track bars and front lower control arms), shock extensions, factory wheels (I haven't noticed the need for aftermarket wheels and the factory ones are lighter than any others I found out there, 37" Nitto Ridge Grapplers, Fox IFP stabilizer, Synergy steering brace and will be regearing to 4.88s in a couple weeks. Overall I have tried to do it right but keep my budget down best I could. It is a super capable truck and will shortly be able to tow properly again with the 4.88s.
 

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Hey folks! I was wondering if eventually you will need to upgrade the Axle's? I have seen some folks recommend upgrading the axle's because of the rolling mass of 37's and above. If your using the stock Dana 44 (Rubicon) can they handle those tires on difficult trails?
 
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Hey folks! I was wondering if eventually you will need to upgrade the Axle's? I have seen some folks recommend upgrading the axle's because of the rolling mass of 37's and above. If your using the stock Dana 44 (Rubicon) can they handle those tires on difficult trails?
Yes, stock Rubicon 44's are VERY strong. They've been proven to handle 37's and even 38's without any real issue. But, anything above a 38" tire, and you'll want to bump up to Dana 60's to avoid the risk of breakage while on the trails. I've broken-down in the past (not in my Jeep) and had to do offroad repairs...Which SUCKS...Espeically when if you had thought it through, you could have avoided it, and done the repairs in a nice shop with a 2-post lift and pneumatic tools, and not laying in the mud or rocks under a risky situation.

If you're mall-crawling, it will be fine for a while, the excess wear will eventually show itself, but not as quickly as fi you're wheeling it and getting tires in binds and catching rocks and roots while tires are spinning. That's what breaks shit inside the axles QUICK.
 
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This is almost my build so I agree with the doing it right but on a budget. I am running a EVO 2.5" Enforcer stage 2 (resulted in over 3" of lift) on my Rubicon (includes front and rear track bars and front lower control arms), shock extensions, factory wheels (I haven't noticed the need for aftermarket wheels and the factory ones are lighter than any others I found out there, 37" Nitto Ridge Grapplers, Fox IFP stabilizer, Synergy steering brace and will be regearing to 4.88s in a couple weeks. Overall I have tried to do it right but keep my budget down best I could. It is a super capable truck and will shortly be able to tow properly again with the 4.88s.
That's the main reason I want to do the 4.88's is to retain towing, and even bump performance slightly higher than stock. A 4.56 puts us at stock gearing with 37's, so 4.88's is a nice bump in low-end performance. :like:
 

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Toying with the idea of 37s. But thinking it’s gonna get pricey. So I’ll need tires wheels (can you use the stock wheels?). And re gear? To what 488 or 5 something? Then a tazer to recalibrate your speedo. And the lift? 2.5 ? 3.5?
So what does it cost? Is it worth it? This is my daily driver mainly an overlander what are your pros and cons and what did you settle on?
I have a 2021 JTR. I went with a JKS J-Venture 3-3.5” lift kit, Yeti Steer Smart Brace, fox 2.0 performance shocks. I re-geared to 5.13s revolution gears. This was recommended by Trail Jeeps who did the install. Instead of 37’s I’d consider the new 38s by Nitto. If you can run 37’s you can run 38’s. I have 37x20” Trail Grappler's M/T. For the lift & gearing & labor it was approx $5300 installed. Add the cost of 5 tires with spare & 20” inch fuel rims probably another 5k+. Not cheap but considering the cost of 40” tires & Dana 60 Axels, replacement of everything underneath it was way better on the pocketbook, Dana 60s alone are 15k. You’ll also need the TAZER JL Mini to set the gear ratio & tire height. My lift component’s are very good & off-road capable but it’s a budget friendly option, there are much higher end lifts, shocks etc but do you need it? I’m more on road than off road, so this lift & gearing accomplishes what I need, nice smooth ride, improved steering, plenty of power (gearing), tough look & off-road capable when I need it. Then you’ll probably want RSE power steps so it’s easier to get in & out of the vehicle.
 
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Since you asked for the right way:

  1. At least a 2.5" + lift with front upper and/or front lower control arms and F&R track bars, plus steering stabilizer.
  2. 4.88 gears for 37s. If you plan on going larger than 37s ever, go with 5.13
  3. Quality aftermarket wheels that are wider than factory and have a slightly more aggressive offset.
  4. JScan, or Livernois Tune, or Tazer, or AEV procal to adjust gear ratio and tire size in the computer.
People will disagree with me, or say they run 40s on the stock axles, but I think that is a recipe for disaster. Even a mall crawler. Bigger, heavier tires will wear out your suspension and drivetrain components much, much faster. If you are off-roading with big tires on the factory axles, you are more likely to break something.

I do not like spacers, they introduce further stress on suspension and drivetrain components. You are shifting the center mass of your very heavy wheels and tires. Also any 12.50 or 13.50 tires will want at least a 8" wide wheel, probably more like 8.5" or 9" wide. Factory wheels are only 7.5" wide.

37s are "fine" with the stock axles and driveshafts, but that is as big as I'd ever go. I'm on 35s.
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