Help with new rims and tires!!!

I am putting a 3 in lift on and was looking at new tires and rims. The rims I wanted are 18 in with a 12mm offset and 5.47" backspacing. the tires I am looking at to put on those are 285/65r18(32.6in diameter) but I am afraid of rub and really don't want to do any trimming...I know I can save some space by going down to a 275/65r18 (32.1in diameter) but those tires are much less common and don't really want to go down to a 265/65r18(31.6in) because that would cut my sidewalls down to just 6.8" when they come with 7.3" sidewalls on the stock tires. I really don't know much about the offset and backspacing truth be told...anyways if anyone has any knowledge on this they can pass my way it would be greatly appreciated

 

You want 4.5" of backspacing to avoid rubbing the UCAs. And if you want a bigger tire you run the risk of rubbing. Chances are you'll only need to trim the inner plastic fender liner which you can do with a pocket knife. You may need to trim the actual fender a bit, but it's easy and it's the inside part of the fender. Can't even see it from 5' away.

From the sounds of it, your wheels are 18x9" which means a -12mm offset to get 4.5" BS and that'll stick out more creating more rubbing and more trimming.

 

I'm running 275/70/17 and was running them for almost a week before my 3" lift was installed. I had minimal rubbing then and zero rubbing now. I believe my wheels are a 4 inch backspacing.

 

the offset of 12mm and the BS of 5.47 are just what the website gave me for my truck when selecting the rims they are 18x9 s