Let's talk optimal build for 31" tires

The clay in the SE will break things most people shake their heads over. It’s stupid simple to get bound up and blow out a front.
I'll definitely defer to you're knowledge on that, I've never been through something like that. But i Imagine with only 31s, there would be clearance and other issues holding the jeep up at the same time? If the clay is that bad and can break shafts with only 31s I'd say chromos wouldn't even be a question?

I didn't know it was that intense.
This is obviously outside the thought process of an overkill build and getting them simply to never have to worry about it.
 
I guess it depends on how hard your beating on it.
If you are the " hammer down" wheels in the air type of driving, , especially in the rocks, maybe chromos make sense.
Shock loading isn't your best friend!
But then what are you using U-joint wise?
There will be a " fuse " in your driveline that show up when you beat on it hard.










i
 
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Having gone down the 33" road, I would mimic this build if I had the opportunity to go back. If I added lockers, and I would, chromos would be part of the build.
 
I guess it depends on how hard your beating on it.
If you are the " hammer down" wheels in the air type of driving, , especially in the rocks, maybe chromos make sense.
Shock loading isn't your best friend!
But then what are you using U-joint wise?
There will be a " fuse " in your driveline that show up when you beat on it hard.










i
No one should wheel without lockers. If you’re running lockers, chromos should go with them.

If by fuse you mean, put there on purpose...Imagine building with the idea that a fuse or the idea that one should install a weak component so that it breaks first is a stupid idea.

Does this idea apply for just us recreational wheelers?
 
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No one should wheel without lockers. If you’re running lockers, chromos should go with them.

If by fuse you mean, put there on purpose...Imagine building with the idea that a fuse or the idea that one should install a weak component so that it breaks first is a stupid idea.

Does this idea apply for just us recreational wheelers?
I think what he meant to say is there is always a weakest link, and if it's the shafts, then you upgrade them, the next weakest link will present itself; Not necessarily that you put a weak part in there on purpose.

late edit for clarity:
Pick your poison - would you rather break a u-joint/CV, axle shaft, driveshaft, or transfer case? If something has to give, one of those will be the weakest link. Think about which one of those is hardest to replace or fix, and which is most expensive, which is the cheapest, and which is easiest to carry spares of.
 
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A significant amount of discussion here is around builds for 33" -35" tires. What if we go in the other direction? Let's hear your thoughts on a build for 31" tires, with a focus on best ride on the street (95% of Jeep use) and best performance offroad (5% of Jeep use).

For offroad, it's important to maintain maximum suspension travel possible.That said, if you were to do an ultimate 31" tire build, what would that look like? Springs, control arms, body lift, shocks, track bars, and more are on the table. Let's hear it. What would your ultimate 31" tire build look like?
Irun, I've been running around Moab this week attempting increasingly difficult trails, and I hunted this thread down again to say that I think you're really on to something here. I've found myself pretty close to what we were talking about, a light and nimble build on 31's. 31.7" tires, full savvy under armor tuck, all aluminum raised skids, and mostly light and nimble - soft top, no back seat, half doors or no doors when offroad. The only other thing is a heavy tire carrier bumper I'll be replacing soon.

I've come to the conclusion that the most impactful upgrades you can give a TJ are lockers and tummy tuck, in that order. Watching everyone at TJ Fest, with driver skill levels and build depths across the whole spectrum, it's apparent how even a heavily built TJ looks pitiful in the hands of a poorly skilled driver, and a mildly built or even close to stock TJ can do much more than most give it credit for in the hands of a skilled driver. Hell, @IBasket has been kicking ass on 31's with a front lunchbox locker over here. Observing all this has me hesitant to move up to 33's, even though I fully planned on that before this trip.

Just some thoughts I wanted to share and add to this discussion!
 
I've come to the conclusion that the most impactful upgrades you can give a TJ are lockers and tummy tuck, in that order. Watching everyone at TJ Fest, with driver skill levels and build depths across the whole spectrum, it's apparent how even a heavily built TJ looks pitiful in the hands of a poorly skilled driver, and a mildly built or even close to stock TJ can do much more than most give it credit for in the hands of a skilled driver. Hell, @IBasket has been kicking ass on 31's with a front lunchbox locker over here. Observing all this has me hesitant to move up to 33's, even though I fully planned on that before this trip.
Nailed it! Having run everything from 29" - 35" tires, 31s are my favorite. If you address the issues of a low hanging belly and gas tank, lock the front and rear, don't build a bloated pig, and sharpen your driving skills, even stock springs and arms will perform admirably. Years ago I had some buddies that gave me crap because I brought my TJ on 31" tires out with them, who were all running 35" tires. I went everywhere they did, with the exception of a couple obstacles, which I knew would result in serious damage. In some cases I went places they couldn't/wouldn't go. When we finished, they weren't giving me crap anymore!

In this case a lot had to do with the driver. I know this because a buddy asked to drive my Jeep and he didn't fair well. He drove it like he was driving a rig on 35s and got hung up several times. This is also another one of the things I like about running smaller tires, you have to pay attention, be more in tune with the vehicle, and know where to position both the rig and the tires.

If your rig is working well, stay focused on weight reduction and making the improvements you need to keep that light and nimble feel, but have the confidence to tackle tough obstacles. Bigger tires aren't always a good thing. When I had a couple Jeeps on 33s, I really wasn't happy.

On my current build, my struggle is the springs. Finding a 2" and under spring with a decent free length is problematic. This also creates an issue when trying to get more suspension travel. My target is a 10" shock travel, but I'm not sure if I'm going to get there. :unsure:

Bottom line to a post that's too long, it's encouraging to hear honest feedback, so thanks for sharing! I've said this before and it should mean something. We won a war with Jeeps on tires that were 28" tall, so we're kind of spoiled now! 🇺🇸
 
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So educate me here, I am running 29 odd inch on 15,s so 31,s give you 1" extra clearance at the diffs and centre skid? if so I dont get the benefit? Really I dont know, my TJ is still factory stock.
 
Nailed it! Having run everything from 29" - 35" tires, 31s are my favorite. If you address the issues of a low hanging belly and gas tank, lock the front and rear, don't build a bloated pig, and sharpen your driving skills, even stock springs and arms will perform admirably. Years ago I had some buddies that gave me crap because I brought my TJ on 31" tires out with them, who were all running 35" tires. I went everywhere they did, with the exception of a couple obstacles, which I knew would result in serious damage. In some cases I went places they couldn't/wouldn't go. When we finished, they weren't giving me crap anymore!

In this case a lot had to do with the driver. I know this because a buddy asked to drive my Jeep and he didn't fair well. He drove it like he was driving a rig on 35s and got hung up several times. This is also another one of the things I like about running smaller tires, you have to pay attention, be more in tune with the vehicle, and know where to position both the rig and the tires.

If your rig is working well, stay focused on weight reduction and making the improvements you need to keep that light and nimble feel, but have the confidence to tackle tough obstacles. Bigger tires aren't always a good thing. When I had a couple Jeeps on 33s, I really wasn't happy.

On my current build, my struggle is the springs. Finding a 2" and under spring with a decent free length is problematic. This also creates an issue when trying to get more suspension travel. My target is a 10" shock travel, but I'm not sure if I'm going to get there. :unsure:

Bottom line to a post that's too long, it's encouraging to hear honest feedback, so thanks for sharing! I've said this before and it should mean something. We won a war with Jeeps on tires that were 28" tall, so we're kind of spoiled now! 🇺🇸
Oh, one more thing I didn’t mention, I’m at 3” of spring lift and 1.25 body lift. I have not cycled my suspension, my bump stops are not set (too much in rear and none in front), and I’m not sure if my clapped out ranchos are even the correct length. That is the next area of my TJ I’ll be focusing on heavily, after lightening up and debulking the rear. I’m excited to see how much better it does after fine tuning with shock choice and correct bump stops.
 
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To make up for the airing down :unsure:
Diffs are still only 1 inch higher than 29,s both aired down or up the same!
Dont get me wrong when I bought my new boots a few weeks ago I should have ordered and waited for a 31" to be delivered to my tire fitter but I thought 31,s were too big for stock height, My fault for not asking first lol