37s too big for DD?

[roaniecowpony]

A racing slick will grip on slick rock though? Rating any tires grip by how it performs on dry slick rock is like rating a vehicles acceleration by driving it off top of the world, everything's fast in a free fall. If you never run loose dirt, mud, or deep snow then by all means an AT is as good or better than an MT. They are definitely better street tires.

When you have a multi-use vehicle, everything is a compromise. The OP said he was going to commute with it. I assumed he meant on pavement. But you may be on to something.

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[chadk77]

I'm running MC 3.5" GC, 37s, regeared to 4.88s, 8 speed auto, and I love it. I drive about 25 miles one way to work and it does great on the highway. I get 16-18 mpg depending how deep my foot is on the accelerator.

WIll probably go to 38s or 39s next time I need tires.

 

[Zandcwhite]

When you have a multi-use vehicle, everything is a compromise. The OP said he was going to commute with it. I assumed he meant on pavement. But you may be on to something.

He also said he currently runs the same stt pro though? I'm guessing he's aware of how they ride on the street, handle in the rain, etc? The 1st time an AT leaves you stranded in the mud where you have to spend hours trying to recover yourself or even worse you have to call for help will be the last time you choose that compromise, or at least it was for us. The wife has commuted on MTs and we've even road tripped from CA to AL and back on them, but some guys are more sensitive I guess?

 

[roaniecowpony]

The OP asked for opinions. Apparently, you're offended by anyone else that differs than yours. Maybe you are the sensitive one.

He also said he currently runs the same stt pro though? I'm guessing he's aware of how they ride on the street, handle in the rain, etc? The 1st time an AT leaves you stranded in the mud where you have to spend hours trying to recover yourself or even worse you have to call for help will be the last time you choose that compromise, or at least it was for us. The wife has commuted on MTs and we've even road tripped from CA to AL and back on them, but some guys are more sensitive I guess?

 

[Zandcwhite]

The OP asked for opinions. Apparently, you're offended by anyone else that differs than yours. Maybe you are the sensitive one.

He asked for tire size opinions, clearly stating his current tire and obvious happiness with its use as he plans to run the same tire even if he goes bigger? You needed to tell him that his current tire sucks for his current use? I‘m pretty sure he disagrees with that opinion, but you do you. The idea than an AT is better off road is just false. As good in the highest traction off road conditions in the world? Maybe but still not better in my experience.

 

[roaniecowpony]

Unfortunately narcissism isn't treatable.

He asked for tire size opinions, clearly stating his current tire and obvious happiness with its use as he plans to run the same tire even if he goes bigger? You needed to tell him that his current tire sucks for his current use? I‘m pretty sure he disagrees with that opinion, but you do you. The idea than an AT is better off road is just false. As good in the highest traction off road conditions in the world? Maybe but still not better in my experience.

 

[Whaler27]

4:88s on 37s is actually a little shorter than stock 4:10s on stock 33s, so 4:88s should be plenty. 5.13s would be better if you towed stuff frequently, but I don't tow anything.

This analysis and the gearing charts finally tipped me in favor of 488s. I have the 8-speed auto-trans and now wish I’d gone with 513s, because my jeep is often overland-loaded and pushing the added wind resistance of a low-profile aluminum roof-top tent.

For the last six weeks the top and all the overland gear has been removed. At 65 mph on the flat I’m in 8th and cruising comfortably and economically at nearly 20 mpg. A barely discernible incline drops me into 7th, as does trying to sustain 73mph on the flat, so my net average in lumpy Oregon is 14 mpg.

With the exception of the power/gearing/mileage concerns, I think the 37s are fine for a DD, but they do add stress and accelerate wear on all the suspension and steering components. It’s also important to remember that as those components wear any resulting wobble will be exaggerated more as tire size increases. I love my 37s, but if I had a couple years of city driving ahead of me I’d mount 35s. (The MOPAR 2” lift has been adequate to run 37s on my jeep. I haven’t rubbed even when pretty flexed. IMO, that lift looks okay with 35s and 37s, so it offers some “flexibility” . For me, a Rubicon with a true 3.5” lift looks a bit goofy on 35s.)

 

[Rubi6mt]

I went from 315/70/17 KO2s to 37/12.50/17 KM3s, on a somewhat heavy built 6-speed with 4.88s (dets in the signature).

The 37s weigh almost 20lbs heavier a piece so round it up to 80lb additional inertia.

When I first drove the Jeep on 37s, I could absolutely feel the increase weight in turning, braking acceleration. However within a few hours I acclimated and completely forgot about it.

I will say aside from the gears, the high inertia CFII flywheel makes the drivability so much better.

For a daily commute, it's definitely doable (I commute like this when I go into the office in NJ/NY/CT traffic), just need to be aware that braking is definitely takes longer.

Offroad it really is amazing what that additional inch or so allows the rig to do.

Personally I'm going back to an AT ture next as up here when there is compacted snow and ice, the KM3s have very little grip. Offroad they are amazing.

 

[3TV]

I'm really interested in the thoughts of those who have 37s on the DD. Other than having to regear and a potential hit to gas mileage, what are the other negatives of moving up to 37s? If I go to 37s they will be 37x12.5
R17 Cooper STT Pros. I currently have 315/70 R17s STT Pros.

I have 37" Cooper STT Pros on my 392 XR, and use it as my daily driver. Best driving Jeep I've ever owned. I did not regear.

 

[Blue Bear]

I run 37" Nitto Trail Grappler MTs on my '23 JLUR 2.0 AT as a DD, and it drives like a sedan. I went 5:38 after talking to the guys at Yukon, and it's been a very good match up.

 

[orange01z28]

I have 37s on my DD

It's fine, feels like the JL/JT platform is made for them. You already know you're going to regear so that's the biggest nut there. Even then, I have the AT and didn't regear until I had had the tires for a month and never felt awful onroad, just felt weak climbing off road

There's 3 real caveats for 37s on your DD
1. Cost of regear
2. Tires are more expensive to replace when you do every 50k miles or so
3. You will end up having to replace steering components eventually

 

[COJeeper]

I run 37" Nitto Trail Grappler MTs on my '23 JLUR 2.0 AT as a DD, and it drives like a sedan. I went 5:38 after talking to the guys at Yukon, and it's been a very good match up.

You wanted them installed at 5:38am?

Anyway..... 5.38 on the 4banger turbo? I have 37" Wildpeak AT3W and they run pretty good on the stock 4.10s with my 4 banger, and I run around ski towns in the Rocky's. I have been debating going between 4.88 and 5.13. One shop recommended 5.13 and said they've never done 4.88s. Another shop said that I'd be good with 4.88 with the 2L. I'm still undecided at this point. It's not bad enough to require the upgrade immediately. This is also my DD.

I have 37s on my DD

It's fine, feels like the JL/JT platform is made for them. You already know you're going to regear so that's the biggest nut there. Even then, I have the AT and didn't regear until I had had the tires for a month and never felt awful onroad, just felt weak climbing off road

There's 3 real caveats for 37s on your DD
1. Cost of regear
2. Tires are more expensive to replace when you do every 50k miles or so
3. You will end up having to replace steering components eventually

You know this is a JL forum, right? GET YO JT OUTTA HERE! I very much kid. I will make an educated guess you have the 3.6. I've never driven a Jeep with the 3.6 on 37s with a lift but I can say you'd be even more surprised about the 2L with 37s. I don't really feel like I lost much at all. However, I understand I am driving a Jeep and not a Ferrari so I'm not expecting a race car anyway.

 

[73TAWM]

I'm going into a local shop this week to get on the schedule for a lift (MC Game Changer). I'm trying to decide between a 3.5 inch lift and moving up to 37s or a 2.5 inch lift and sticking with 35s. I know that 37s will require a regear and will go to 4:88s if I go that route. This is for my DD JLUR 6MT. I have about a 40 mile round trip commute each day.

I don't wheel much around home because the options are pretty limited but I do get to Moab once or twice a year and hopefully will be moving out west in the next few years.

I'm really interested in the thoughts of those who have 37s on the DD. Other than having to regear and a potential hit to gas mileage, what are the other negatives of moving up to 37s? If I go to 37s they will be 37x12.5
R17 Cooper STT Pros. I currently have 315/70 R17s STT Pros.

I lifted my 21 rubi with a 2.5" lift from Dynatrak. With the factory 33s it drove a little wonky and felt off center going down the road, turning, etc. Once I added the 37s BFG/AT it went back to handling like factory. I have not changed the gears from 4.10 yet but we took it out to Colorado last year and went everywhere, off road included and it did great. It is now my daily driver 40 miles per day and it does great. I will eventually re-gear but not because I am noticing any struggles. Pic for reference.

 

[Panda Mafia]

OP I was once in your shoes. Someone on here told me if you even have a thought of 37 then just do it right away. Skip 35s. What that person did not tell me is that I would want to go even bigger after that lol. Thank god Ive listened.

 

[JeepinPete]

I've been running 37" BFG KO2's for the last 25k miles, 20k of that with no lift, the rest with the Dynatrak 2" lift. 6spd, 4.10 gears. Does fine and somehow did not affect MPG at all (I record every tank). I may swap gears some day, but do not think it is mandatory.

Pete

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