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A probably-stupid tire question

Nimrod

Degenerate Jeeper
NAXJA Member
Location
Duck River
I've long wanted to move up from 33 to 35-inch tires. But storing a 35" spare would be a problem for me. I'm running a selectable Ox locker up front and a Detroit Eaton in the rear. What would happen if i ever had to throw on a 33" spare with a set of 35" tires? I'd imagine that putting an odd size tire in front, even as a temporary measure, would cause a problem with steering. But what would be the effect of throwing the odd tire onto the rear with an auto locker? Anyone done it?

Any thoughts, as soon as possible because a deal has come up on some tires, would be much appreciated!
 
can't run odd size tires in the back with the auto locker. could put spare on front and make sure you don't engage the locker.

obviously, best bet would be same size tires...
 
Cal was polite enough to PM me and tell me back-channel what a stupid question this was. Lol!

Anyway, thanks. I've got my answer. Gonna pass on the tire upgrade for now.
 
If you modified the rear seat back brackets and shifted the back forward 2-4 inches, you'd have enough room to lay a 35 down in the back and still have a rear seat. Or you could modify the back of the seat by putting a tire sized divot in the middle allowing the tire to slide into the seatback while the tire is flat.
 
If you modified the rear seat back brackets and shifted the back forward 2-4 inches, you'd have enough room to lay a 35 down in the back and still have a rear seat. Or you could modify the back of the seat by putting a tire sized divot in the middle allowing the tire to slide into the seatback while the tire is flat.

Hah. Literally what I said in my PM.

One of the locals and old school naxja member had done exactly that.
 
I like the idea of making a cut-out in the back seat to accommodate the bigger tire. I've got my 33x12.5 spare laying flat in the cargo compartment now, with a tray on top to hold ice chests and bins and stuff. I'll add this mod to the bottom of my very, very long to-do list, and will shoot for getting it done and upgrading to 35s before Moab next October.
 
If you modified the rear seat back brackets and shifted the back forward 2-4 inches, you'd have enough room to lay a 35 down in the back and still have a rear seat.

I read a write-up on that some time ago, but only the top brackets of the backrest were relocated. That was to accommodate a 31 inch (if I recall correctly) tire mounted upright in the factory spare tire location. Moving just the top of the backrest forward wouldn't make space for a tire laying flat on the deck, and moving the entire seat forward two inches (including the bench and the backrest) would be a major undertaking I would think, requiring way more engineering and fabrication than it could be worth. I'd sooner just remove the back seat altogether and consider the rig forevermore a two-seater. That's my thought anyway.
 
You can fit a 33" tire in the back stock tire location, you just have to remove the step on the ground that help the smaller stock tire and deflate the spare down to 10-15 psi. That was what I did till I got a tire carrier on the bumper.
At about 10 psi you could latch the back seat no problem but anymore and you might want to relocate the larch bracket on the body.
35" you can lay on the ground but it's always easier if the tire is deflated a bit for squishing


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35 will fit standing up, that's where mine is temporarily until I finish my rear bumper.

Downside is blocks visibility, and tie down points aren't convenient.
 
I pulled a vacuum on my 35 and made it square.The back seat still works.
 
can't run odd size tires in the back with the auto locker. could put spare on front and make sure you don't engage the locker.

obviously, best bet would be same size tires...

bad plan.

even in an open dif, the spider gears will fail rather quickly.
 
A 33" inflated tire will fit in the stock location with a little modification.
8423705267_60779b6835_m.jpg

Details here.
https://www.flickr.com/photos/lwade/8423705267/in/album-72157623364828871/
 
A 35x12.5 will fit in the back laying down. You dont need to mess with the back seat latch or hinge. Just take a good size hammer and hit the back of the seat in the area of the tire. The backing is thin steel and will dish in with only a few hits. No ugly seat holes no messing around with moving the seat or anything. Its going to feel a little funny for who ever sits in that spot but the tire fits.
 
even in an open dif, the spider gears will fail rather quickly.

Simply not true! When a open diff spins the wheels they are turning the spiders much much faster than it would with a unequal size tire in full contact with the road. Do you realize how many vehicles I see everyday with mis-matched tires!
 
Simply not true! When a open diff spins the wheels they are turning the spiders much much faster than it would with a unequal size tire in full contact with the road. Do you realize how many vehicles I see everyday with mis-matched tires!

"simply not true!"

when the ring gear turns an open diff and both shafts are loaded equally... the spiders do not spin. they only spin in situations of uneven load, such as negotiating a turn. mismatched tires would like being in a constant turn. the spiders run on thrust washers, not bearings. they would fail.
 
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Can't we all just get along?

Seriously though, thanks to all who responded. I've got all the info I need.
 
not a plan, its a response to a question. Would it get OP off the trail? yes it would.

true. it would get you a few miles. I would certainly inspect the spiders and replace the thrust washers when I got it back.


Simply not true! When a open diff spins the wheels they are turning the spiders much much faster than it would with a unequal size tire in full contact with the road. Do you realize how many vehicles I see everyday with mis-matched tires!

how many vehicles do you see with tires with a 2-3" difference in diameter?

I can assure you it is absolutely true. the spiders will fail and they will fail quickly. I wouldn't drive more that 10 miles that way.
 
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