When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I run some 'wheel adapters' on my '00 F350 dually. They add 2 1/2" space between the wheels and let me use a BF Goodrich 295x75, I think that's about a 33 inch tire, pretty wide too.
Not sure the brand, but they are out there, I would think an offroad/custom truck shop would be able to help you find them. Think I paid a couple of hundred $$ a piece for mine. They are kind of a pain in the a#$# when you get a flat too.