smiller

2014 JK Rubicon with about a 2" lift (may actually be more like 1" in the front due to bumper and winch), extended bump stops, and 17x8.5 wheels with 5" backspace. Current tires are 305/65R17 and there is no rubbing under any conditions. Will I likely be OK to go up to 285/75R17? (looking for a true 33" tire) Note that I mean 285/75R17, not 285/70R17. Also gearing is 4.10 and not looking to change it, from what I can research 4.10 should be adequate for 33's? (auto trans)

Thanks

bbolander

I have a 2012 JKUR with a Mopar 2" lift. I have the 285/75R17 BFG MT's on 17x9" wheels with 4.5" backspacing. And 4:10 gears, auto trans. I like your idea of 8.5" wheels (or even 8") with 5" back spacing. I don't do severe articulation but haven't had any rubbing issues. I don't like the tires sticking out about 2" beyond the flares. Don't like the look. Don't like the dirt slinging all over the side of the Jeep when I hit a puddle or dirt from a dirt road after the rain.

smiller

Thanks for the pics, nice rig. I'm still not certain how much lift I have but my tire clearance to the fenders seems similar to yours so at least I'm in the ballpark.

Michael Martin

cadenajeepjk

Great Looks,.. I´m really like your jeep.... I´ve a 2 Doors Sahara with 275/70/17 on OE Rims (with minor rubs while full turn) and I´m going to install 2.5 lift kit this week, I´m not sure if I will need to install spacers, do you have spacers?
Again congratulation Great set up !!!

Best Regards

Michael Martin

jedg

The wheel spacers don't have much to do with the lift. The spacers are required because the wheel doesn't have enough backspace to push the tire out enough to keep it from contacting the lower control arm typically. For example, when you turn full lock to the driver side, the back of the driver side tire will sometimes rub the driver side lower control arm. Pushing the wheel out (increasing back spacing) will keep that from happening. Now, this also means you could be rubbing part of your fender (lower piece of it closest to your front door) on that same driver side. A lift sometimes helps with that, but normally it's the LCA that is the reason for the spacers.

smiller

So basically, wheel spacers or backspacing is more to allow for tire width, not height?

nthinuf

Both width and height. With the same 12.50 width, a 35" tire will contact the frame/components before a 33". In his Thoughts on Lifts thread, Dirtman notes these general recommendations.

Net max back spacing:
5.5” for a 33x12.5
4.5” for 35x12.5
3.5” for 37x12.5
1.75” for a 40x13.5

Also remember that with lower effective backspacing, the tires are pushed out further so they no longer tuck up inside the fenders. This makes it more likely to contact the lower lips on the stock fenders. So lift height, tire height and width, bumpstop height, effective backspace, flare choice, whatever else, are all mixed together. Unfortunately, it is more of a case-by-case thing, not a one-size-fits-all answer.

bbolander

That's interesting. Interpolating for the 34" tires we're discussing means a 5" back spacing. Since the tires we're discussing are about 11.5" wide, that's another 1/2" so we could go with a 5.5" back spacing. If I had 8" rims rather than 9" rims, that picks up another 1" on the outside. So 5.5" back spacing with 8" rims should put the outside edge of the tire close to the outside of the fender and prevent the mud splashing all along the side of the Jeep and the tire contacting the fender lower lip. Compared to my setup with 4.5" backspacing and 9" rims which puts the outside edge of the tire about 2" beyond the fender.