Trying to find out how do you know what your stock rims backspacing is and where do you find out how much backspacing you would need for a specific size rim if you install a leveling kit 2.5" Not sure what rim or tire size I will go with because not sure what size I would be able to fit. I have an 05 Super cab 4x4

 

Stock backspacing is 5.5".

 

Also, your oem wheels are 7.5 inch wide. I'd suggest using a 33 inch tire and a 9 inch wide wheel with 5 to 6 inches of backspacing.