The 255s are 10.4" wide. I put on some 285s (11.2") and had slight rubbing. The stock rims are 7.5" wide and 285 is about the largest that is the "recommended" by manufacturers. Some/most shops won't put anything wider on the stock rim.
1) 1.5" adapters(otherwise known as spacers-around $200) will give you up to 13.5" width and puts the inside sidewall at the same place as stock. BUT, with bigger tires and sticking out further (because wider) fender rub comes into the picture.
2) New rims with 4.5" backspacing-$500 on up again fender rubbing
2.5" lift, 285s. 4.5bs and stock fenders
not even that big a mound
Now options after getting fender rub:
1) Flat fenders around $600
2) Cut fenders $0 other than time
Flat fenders don't seeing myself rubbing with the 285s
I personally went though all these steps.
285 got rubbing -> adapters then rims(because I could, should have done it in the beginning) -> lift -> still got some fender rub -> flat fenders.
I wish I never would have lied to myself about lifting, tires, rims etc. and done it right the first time.
Here is some interesting reading