What wheel size and backspace will I need?

D

Datman

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May 15, 2019
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louisiana
OK guys, this is a hard post for me.....but here it goes.....Ive always loved the look of a TJ with thornbirds sticking out from the fender flares and Im trying to decide what wheel and backspace i would need to really have them kicked out a good bit.....Im looking at 33x12.50/15 thornbirds with either a 15 x10 or 15x8 wheel... I have looked and looked and looked and cant really find a good pic that also has info on what size wheel and backspacing i need to really get the look im going for. Im in south louisiana so im not dealing with snow or rock climbing...Im getting the ultimate OEM lift from DPG..... Theres just something about them thornbirds on a TJ sticking out a few inches from the fender flare that I absolutely love.....
Does anybody know what backspace i need to get the look Im after? anybody have any pics of thornbirds that show how far they are sticking out?

Im fully aware that you guys are gonna laugh at me, but thats what I want..
This is not a daily driver, just a run around town and the occasional mud ride

PS. I had 33x12.50 thornbirds on my 1990 4runner w/ 3" inch lift 20 yrs ago and I never really got stuck...They total changed the capabilities of that 4runner...I would walk all around the z71s at the time.
 
Your vehicle, your choice on tires. Just run a 15x8 wheel with 3.75" to 4" of backspacing and you'll be good to go.
 
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Irun said:
Your vehicle, your choice on tires. Just run a 15x8 wheel with 3.75" to 4" of backspacing and you'll be good to go.
Click to expand...

do you have a pic showing how far that will kick out a 12.5 wide tire? I just dont think thats gonna kick out the tire wide enough for me
 
There's a limit to how little offset can be run. Generally anything below -0.5" of offset (3.5" backspacing on a 15x8) is going to significantly increase bearing and ball joint wear. In addition the wider you go, the worse the handling is going to get due to the increased scrub radius.

I recommend going no less than 3.25" of backspacing. 3.75" would be safer. On a stock TJ, 3.25 should result in about 3.5" of tire tread sticking out past the fender flares. If you want the really wide look, remove the fender flares and install aftermarket front fenders.

You can even get "negative" fenders which are actually narrower than stock fenders with no flares. This would be the best way to get the exposed tire look without going to wider axles.
https://shop.poisonspyder.com/TJ-LJ-Defenders-Negative-Flares-Steel-p/14-02-050.htm
Beyond that, and it would be significantly safer to install wider axles. JK axles are ~5" wider. That will require some fabrication skills (or a lot of cash) to do. Beyond that you'd be looking into full width Dana 60 axles, at which point you're building a rock crawler.
 
Steel City 06 said:
There's a limit to how little offset can be run. Generally anything below -0.5" of offset (3.5" backspacing on a 15x8) is going to significantly increase bearing and ball joint wear. In addition the wider you go, the worse the handling is going to get due to the increased scrub radius.

I recommend going no less than 3.25" of backspacing. 3.75" would be safer. On a stock TJ, 3.25 should result in about 3.5" of tire tread sticking out past the fender flares. If you want the really wide look, remove the fender flares and install aftermarket front fenders.

You can even get "negative" fenders which are actually narrower than stock fenders with no flares. This would be the best way to get the exposed tire look without going to wider axles.
https://shop.poisonspyder.com/TJ-LJ-Defenders-Negative-Flares-Steel-p/14-02-050.htm
Beyond that, and it would be significantly safer to install wider axles. JK axles are ~5" wider. That will require some fabrication skills (or a lot of cash) to do. Beyond that you'd be looking into full width Dana 60 axles, at which point you're building a rock crawler.
Click to expand...


I appreciate the advice. Def looking to keep the stock fenders and Im not trying to do anything that crazy.......Thanks for the advice on the backspacing
 
3.75” of backspacing is gonna give you plenty of stick out on stock flares. Trust me. With 12.5” tires mine would stick out 4 inches past the stock flares if I didn’t have a Rubi or aftermarket flares. Is 4” out enough??
 
Make sure to stretch them onto wide wheels
 
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Chris said:
What the holy hell is a thornbird?

A Greta Thunberg?
Click to expand...
Interco tire...don’t look quiet :)
5E4B287B-0B91-4106-8B71-C8A904BC28F5.jpeg
 
BuildBreakRepeat said:
3.75” of backspacing is gonna give you plenty of stick out on stock flares. Trust me. With 12.5” tires mine would stick out 4 inches past the stock flares if I didn’t have a Rubi or aftermarket flares. Is 4” out enough??
Click to expand...

Id like 6"...LOL..wait....thats what she said!
 
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