Ford Repair: Tire Size, tire size, warranty

Question
What is the biggest tire size you can put on a 2012 f150 XLT supercrew without getting it lifted.

Answer
to be perfectly honest. i wouldn't go any bigger other than whats on it without consulting your local dealer. reason being in 1, you could very easily void your warranty. 2, you would need multiple modules in the truck recalibrated to compensate for tire size