I just bought a new 08 4x4 F150 and want to put on a set of 20" and larger tires. I a looking to buy the american racing mace machined black wheels 20x8.5 but I am unsure about the backspace and offset. They are eighter 5.34 backspace and 15 offset or 4.99 backspace and 6 offset. I have been reading through this forum and others and I am still confused on which one to get. I do not want the tires to stick out past the fenders so which one should I go with. Also my tires will be 275x65's, any help is appricated.

 

from what i know about this, there both going to stick over a bit. i just posted something on this yesterday. search "rims"

 

A minus offset pushes the wheel out and a positive offset brings the wheel in. My wheels have a +10 offset. The wheels stick out about an inch. Check the pictures in my album. Have the store where you buy the wheels put one on the front for you before you buy!!