Backspacing and lifts

JlChris

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I recently purchased but have yet to install a 3.5 inch rock krawler adventure series lift. On their website they recommend 3.5" backspacing when running 37s. What is the reason for this? Is it rubbing on the control arms? The only wheels that I can find with 3.5" backspacing are beadlocks (which I don't want). Will 4.5" bs wheels work with this lift?
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whiskey jack

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On my RK I ran into the same dilemma. I ended up running 4.75 backspacing on 37/12.5s and have plenty of space between the tires and the (i think) trouble area which is the rear anti-sway bar links. I also haven't noticed any rub on the rear inner tubs.
 

Rock Krawler Suspension

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I recently purchased but have yet to install a 3.5 inch rock krawler adventure series lift. On their website they recommend 3.5" backspacing when running 37s. What is the reason for this? Is it rubbing on the control arms? The only wheels that I can find with 3.5" backspacing are beadlocks (which I don't want). Will 4.5" bs wheels work with this lift?
On a sport, you have narrower axles than a Rubicon so what @whiskey jack mentioned is not accurate for your jeep and your situation. 3.5" BS is the recommended BS to alleviate rubbing concerns. Do some people cheat the numbers, sure. Every wheel manufacturer is a hair different and every tire manufacturer is different so getting an exact number to publish is not possible. Target close to that BS and adjust steering stops if needed.

There are tools out there to measure your exact back space requirement with your particular tire if you want to. Just search for backspace measuring tool on google.
 

rayzjeep

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I have a Rubicon with 4.5" backspacing (Trail Ready Bead locks) and have rubbing on the lower control arms at full lock. I have the 2.5" RK lift and tires are 12.5 wide 37s. Rubbing isn't much and only at full lock so I just kind of live with it...doesn't really hurt anything.
 
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