18 JLUR 33s to 37s this week - perspectives?

[Rb75]

I've been adding some capability to my JL Rubicon since I bought it, but now it was time to replace my tires I decided to step up to 37s. The install is under way, but curious this groups take. 2 days after the install I'm heading out to a multi-day event, so I want to make sure I'm set up.

• 37" Maxxis Razr AT (12.50x17LT)
• Keeping stock JL wheels for now with 1.75" spacers
• 2.5" Rubicon Express lift (Already have Fox 2.0 IFP shocks)
• Teraflex Alpha Adjustable HD carrier
• ARB classic stubby bumper (currently have classic full size, shifting over Smittybilt winch, ProComp lights)

Questions:

• 2.5" lift going to be sufficient to avoid any rubbing on fenders, shocks, etc?
• Regearing? I'm going blind reading threads that range from big issues to zero issues. Think this setup will be fine without regearing given what I've got on the Rubicon?
• Hinge Reinforcement? Again, going blind reading threads with perspectives, but at this point I'm just installing the TeraFlex carrier. I'm adding about 22lbs of weight with the new tire/existing wheel setup.
• 4WP Tire Warranty? I typically avoid warranties but considering the $200 to cover any tire damage. Anyone have experience with a claim at 4WP?

This is my daily driver, I spend about 90% on the road, city driving. I try to get out to Tillamook State Forest as much as I can, and have a couple of trips set up for this year. Mostly moderate trails, no intent for crazy rock climbing.

In terms of previous upgrades... Fox 2.0 IFP shocks, 1.5" Teraflex spacer, Ace rock sliders, ARB onboard air, Smittybilt X20-10k, Oculus LEDs, Artec aluminum skid plates

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[aldo98229]

Another perspective:

 

[Some Random Guy]

I've been adding some capability to my JL Rubicon since I bought it, but now it was time to replace my tires I decided to step up to 37s. The install is under way, but curious this groups take. 2 days after the install I'm heading out to a multi-day event, so I want to make sure I'm set up.

• 37" Maxxis Razr AT (12.50x17LT)
• Keeping stock JL wheels for now with 1.75" spacers
• 2.5" Rubicon Express lift (Already have Fox 2.0 IFP shocks)
• Teraflex Alpha Adjustable HD carrier
• ARB classic stubby bumper (currently have classic full size, shifting over Smittybilt winch, ProComp lights)

Questions:

• 2.5" lift going to be sufficient to avoid any rubbing on fenders, shocks, etc?
• Regearing? I'm going blind reading threads that range from big issues to zero issues. Think this setup will be fine without regearing given what I've got on the Rubicon?
• Hinge Reinforcement? Again, going blind reading threads with perspectives, but at this point I'm just installing the TeraFlex carrier. I'm adding about 22lbs of weight with the new tire/existing wheel setup.
• 4WP Tire Warranty? I typically avoid warranties but considering the $200 to cover any tire damage. Anyone have experience with a claim at 4WP?

This is my daily driver, I spend about 90% on the road, city driving. I try to get out to Tillamook State Forest as much as I can, and have a couple of trips set up for this year. Mostly moderate trails, no intent for crazy rock climbing.

In terms of previous upgrades... Fox 2.0 IFP shocks, 1.5" Teraflex spacer, Ace rock sliders, ARB onboard air, Smittybilt X20-10k, Oculus LEDs, Artec aluminum skid plates

Your first question has a 3 part answer. First, a 2.5” lift will clear at ride height. Bumpstops are what prevent contact offroad (full stuff, flexed, other terms). Your lift probably has a guide to how much bump to install or just has a 2-3” set which will work for 37’s. Finally, your wheel backspacing and lift kit combined determine contact with suspension (control arms and/or shocks). You have wheel spacers to address the 3rd point.
Regearing will make your driving experience better but is absolutely not necessary to enjoy your plans. I would make sure the Jeep is reprogrammed for tire size first, then worry about regear later. The auto is less sensitive to gearing than the manual.
I wouldn’t worry too much about hinge reinforcement. But do make sure your tire clears your rear bumper and has the appropriate sized tire stops to hold the tire still on the tailgate. There are some options out there that replace the stock hinges to remove all worry.
I can’t speak to 4wp’s warranty, I do my own installs including tires.

 

[kah.mun.rah]

• 2.5" lift going to be sufficient to avoid any rubbing on fenders, shocks, etc?
• Regearing? I'm going blind reading threads that range from big issues to zero issues. Think this setup will be fine without regearing given what I've got on the Rubicon?
• Hinge Reinforcement? Again, going blind reading threads with perspectives, but at this point I'm just installing the TeraFlex carrier. I'm adding about 22lbs of weight with the new tire/existing wheel setup.

Yes, 2.5" lift with the Rubicon is sufficient for 37s. Depending on how much weight you add in the back you might rub the back side of the rear fender liners when hitting bumps but it's not a big deal. If it becomes an issue that part of the rear fender liner is removable.

Re-gearing is not necessary with an 8 speed auto trans and 4.10 with 37s but to get the stock RPMs you might want to put it on the future to-do list.

I have run a very heavy 37" tire on a JK and two JLs with stock gate hinges with zero issues. Many people say that 37" is where the hinges need to be reinforced but in all of these years I have never meet someone that actually had a real issue.

 

[Rb75]

Your first question has a 3 part answer. First, a 2.5” lift will clear at ride height. Bumpstops are what prevent contact offroad (full stuff, flexed, other terms). Your lift probably has a guide to how much bump to install or just has a 2-3” set which will work for 37’s. Finally, your wheel backspacing and lift kit combined determine contact with suspension (control arms and/or shocks). You have wheel spacers to address the 3rd point.
Regearing will make your driving experience better but is absolutely not necessary to enjoy your plans. I would make sure the Jeep is reprogrammed for tire size first, then worry about regear later. The auto is less sensitive to gearing than the manual.
I wouldn’t worry too much about hinge reinforcement. But do make sure your tire clears your rear bumper and has the appropriate sized tire stops to hold the tire still on the tailgate. There are some options out there that replace the stock hinges to remove all worry.
I can’t speak to 4wp’s warranty, I do my own installs including tires.

Helpful feedback, thank you!

 

[Rb75]

Yes, 2.5" lift with the Rubicon is sufficient for 37s. Depending on how much weight you add in the back you might rub the back side of the rear fender liners when hitting bumps but it's not a big deal. If it becomes an issue that part of the rear fender liner is removable.

Re-gearing is not necessary with an 8 speed auto trans and 4.10 with 37s but to get the stock RPMs you might want to put it on the future to-do list.

I have run a very heavy 37" tire on a JK and two JLs with stock gate hinges with zero issues. Many people say that 37" is where the hinges need to be reinforced but in all of these years I have never meet someone that actually had a real issue.

Thanks - re: the reinforced hinges, I found a lot of perspectives but no posts about real issues either.

 

[kah.mun.rah]

Thanks - re: the reinforced hinges, I found a lot of perspectives but no posts about real issues either.

Yep. This guy put his JL through much more than most of us ever will and gives a review of his 37 with a stock tailgate if you haven't come across this yet:

 

[Rb75]

Yep. This guy put his JL through much more than most of us ever will and gives a review of his 37 with a stock tailgate if you haven't come across this yet:

I had not seen that, I'm feeling better about just the tire carrier / no reinforcement

 

[Bill_P]

Another perspective:

That is the very first thing that came to my mind.

 

[Rb75]

That is the very first thing that came to my mind.

I suppose if MPGs were my priority I’d be a member of the Prius forum instead of this one. I gave up on good gas mileage years ago when I bought a big box to drive around in! Having said that, current prices are going to sting a bit more.

 

[iddpaul]

Questions:

• 2.5" lift going to be sufficient to avoid any rubbing on fenders, shocks, etc?
• Regearing? I'm going blind reading threads that range from big issues to zero issues. Think this setup will be fine without regearing given what I've got on the Rubicon?
• Hinge Reinforcement? Again, going blind reading threads with perspectives, but at this point I'm just installing the TeraFlex carrier. I'm adding about 22lbs of weight with the new tire/existing wheel setup.
• 4WP Tire Warranty? I typically avoid warranties but considering the $200 to cover any tire damage. Anyone have experience with a claim at 4WP?

This is my daily driver, I spend about 90% on the road, city driving. I try to get out to Tillamook State Forest as much as I can, and have a couple of trips set up for this year. Mostly moderate trails, no intent for crazy rock climbing.


I'm driving a 2020 JLUR, 3.6, auto, 37"s, bead locks, tazer, winch, bumpers, etc., etc. (pretty much my DR)

I agree - "your wheel backspacing and lift kit combined determine contact with suspension (control arms and/or shocks)"

Also rubbing on the liner should be controlled by the bumpstops and the specific lift adjustments, but in my case with a 2.5" lift and 37's on the trail, with good articulation, I was rubbing pretty hard, sometimes really hard, on the rear fender liners.

The solution for me was to use a heat gun and "re-form" that part of the liner (I could have gone with an aftermarket replacement or just removed that piece), and I then used it as reasoning (to myself) to install a 3.5" lift. Super happy with the lift for both road and trail handling.

Good luck on the gearing issue, as there are more comments on the site than you can read (haha). For me, I started with a 2.5" lift, 35's and 4:10's, then moved to 37 Ridge Grapplers/Bead Locks and 4:10's for about 8 months. I'm in FL, so not much elevation, and have to drive a bit to hit the trails and forest roads, etc. So 4:10's and 37's are drivable, but didn't see 8th gear much, on a trip couldn't hold 8th with any incline or a head wind, was sluggish starting off and marginal mpg. A gear change is the BEST mod I've done to date, period. I would advise either 4:88's or 5:13's dependent upon your use/environment (do the math but you also must account for rolling mass, extra weight for aftermarket goodies and what/where you'll be going (highway, trail, rocks or a combo).

I did have the Mopar tailgate reinforcement, so didn't have to change out the carrier, but after adding all the extra weight decided on making a change and adding Hinge Reinforcement. Great peace of mind and I can hang extra's out back now.!

I'm not a big believer in a tire warranty and have gone through a bunch of tires over the years, so that's really your call...best of luck..!

 

[lashlee]

I just put a MC GC3.5 on my wife's JL 2.0 with a 37x12.50's with stock gearing. She took a trip last weekend and got 16.4 mpg while cruising at 77 mph on the interstate. We've wheeled it a couple of times over the last few weeks and have yet to rub anywhere, using stock fenders and liners.

Her's has the tailgate reinforcement but I've got a Motobilt carrier at the powder coat shop as we speak because her tailgate is already sagging. That may be from the original install so I won't say it's due to the new wheel/tire package. I will say it moves around quite a bit on the trail!

Either way, it will be quite a change, and you'll dig it!

 

[kah.mun.rah]

One more comment on the re-gear. How many miles do you have on your Jeep? The 2018 (and possibly other years) are famous for having locker sensors go bad. If you re-gear and are still under warranty, that is one thing to consider since it might void your warranty for repair. For this reason I am getting along fine with the 4.10 and 37s and then will improve the ratio once my warranty is up.

 

[Rb75]

One more comment on the re-gear. How many miles do you have on your Jeep? The 2018 (and possibly other years) are famous for having locker sensors go bad. If you re-gear and are still under warranty, that is one thing to consider since it might void your warranty for repair. For this reason I am getting along fine with the 4.10 and 37s and then will improve the ratio once my warranty is up.

Thanks for thinking of this but I went off warranty last year.... one of the reasons I waited until now to get into this upgrade!

 

[Brock9281]

I've been adding some capability to my JL Rubicon since I bought it, but now it was time to replace my tires I decided to step up to 37s. The install is under way, but curious this groups take. 2 days after the install I'm heading out to a multi-day event, so I want to make sure I'm set up.

• 37" Maxxis Razr AT (12.50x17LT)
• Keeping stock JL wheels for now with 1.75" spacers
• 2.5" Rubicon Express lift (Already have Fox 2.0 IFP shocks)
• Teraflex Alpha Adjustable HD carrier
• ARB classic stubby bumper (currently have classic full size, shifting over Smittybilt winch, ProComp lights)

Questions:

• 2.5" lift going to be sufficient to avoid any rubbing on fenders, shocks, etc?
• Regearing? I'm going blind reading threads that range from big issues to zero issues. Think this setup will be fine without regearing given what I've got on the Rubicon?
• Hinge Reinforcement? Again, going blind reading threads with perspectives, but at this point I'm just installing the TeraFlex carrier. I'm adding about 22lbs of weight with the new tire/existing wheel setup.
• 4WP Tire Warranty? I typically avoid warranties but considering the $200 to cover any tire damage. Anyone have experience with a claim at 4WP?

This is my daily driver, I spend about 90% on the road, city driving. I try to get out to Tillamook State Forest as much as I can, and have a couple of trips set up for this year. Mostly moderate trails, no intent for crazy rock climbing.

In terms of previous upgrades... Fox 2.0 IFP shocks, 1.5" Teraflex spacer, Ace rock sliders, ARB onboard air, Smittybilt X20-10k, Oculus LEDs, Artec aluminum skid plates

What 2.5 lift did you use? Link? How’s it ride on road with the Fox 2.0?

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