I'm shopping for a bigger wheel/tire combo for my Fx4 Reg Cab LB Gas Snow Plow/ Camper package optioned work truck. It has:
7.5 X 17" Cast Alloy Wheel
LT245/75/R17E A/T BSW

What I don't know is the offset and backspace. I'm thinking of a 285/75/18 tire and want a wheel that will make it fit right. Anyone out there working with what I'd like? I'm looking at putting on Method Wheels

 

40 is factory offset. A 15 offset would move the wheel out appox 1" for reference, if you keep a 7.5 rim. If you go with 9 inch rims your tires will move out 1.750 approx

 

The +18/20mm wheels do the best for keeping tires under the fender. The zero offset wheels will stick out and throw more road gunk on the truck.