Wheel offset

Ok. I'm not sure what size my lift is. I bought the truck this way. Im guessing its an 8+. Anywho my tires rub on my leaf springs bad. I maybe get 60% of my turning radius. From what I found researching my rims only came in 0 and -10 offset. They seem like 0 to me by eye guage.

Is gettin some super offset rims the only way to run 40's on an 04?

Sorry if this is stupid Q.

Don