I have a 2007 F150 Crew 4x4 and want to install MB Gunner wheels 17x8. What is the biggest tire I can fit?

 

I'd go with a 305/65-17 (33x12.50). Also, be sure to test fit one of the wheels first. Ford changed brake caliper design during the 2005 model year and this is causing fitment problems with some, but not all, aftermarket 17 inch wheels.