Minimum backspacing to clear UCA's

I'm starting to look for new wheels and tires for my 2010 tacoma. I will be installing a 3 inch lift in the spring and I will be getting 285/70 17's. What backspacing do I need on the wheels to clear the factory UCA's without having any rubbing issues.

 

4.5" is a good rule of thumb, though the absolute max backspacing you can use and still clear the ucas also depends on the width of the wheels. For instance folks running 9" wide wheels can get away with 5" of bs.

 

I'm running 16x8 with 4.8 bs. Could these clear uca with 285 75r16?

 

You also have to put in the offset of the rim