2005 Dually tire size options

[dzldoctor]

Guys looking at tires for 05 f350 dually. Stock size is 245/75/17. Looking just a slightly larger tire without issues on the dually. Keeping the stock wheels.

 

[slowcoupe]

I run a 285/70/17 on my 05 dually with just a wheel spacer in the rear on stock 17's.

 

[dzldoctor]

Spacer between the duals?

 

[Horsemover]

I run a 285/70/17 on my 05 dually with just a wheel spacer in the rear on stock 17's.

How wide of a spacer?