285's and jba are rubbing

I have 285 70 r17 with jba uca.
Wheels are 17x8.5 0 offset 4.75 back spacing. I rub on the uca when the steering wheel is turned all the way or close to it .

I thought this combo was safe from rubbing

Per website:11.2" wide tire, if the wheel is 8.5" wide, you need a 4.75" backspace or smaller to clear the JBA ucas.

 

Unfortunately you made the assumption that the tires size is exact. Per the website you would have 1/8” of clearance if the tire section is exactly 11.2 wide. If it’s a bit wider it will rub. Not a lot of room for error. I’ve seen 285s run as much as 1/2 - 3/4” taller and wider.

 

yeah and apparently I chose a pretty aggressive AT tire that is wider and has side biters. MT Baja Boss AT. It's only slightly at full lock so I think if I just be mindful of that I should be able to avoid it most times. Or try to find a 1/4 inch hubcentric spacer and hope I don't need longer wheel studs.

When I was shopping tires, UCA rub wasn't even on my radar, I was all about BM rubbing.