will 265/75/R17's fit on rear of dually or will a spacer of some kind be needed?

 

Depends on the tire. Some are wider then others even if they have the same measurement on the side. I got 255/85/r16s on mine with about 3/4" at the buldge.

 

oops they are 265/70/17E I guess the rims are 17x6

 

Hey Fury, I've walked this road already, and haven't really come up with a good answer yet. Yeah, 265's are available for our 17's but it's the general consensus that wheel spacers will be required. I'm not personally in favor of that, so I've got some 19.5 Weld Racing rims on order. They're a bit pricey, but ya got something when said and done. Below is the link to Rons Rims.
He's got a decent price, just a big back order.
http://www.ronsrims1.com/Ron%27s%20Rims/Welcome.html

Good luck on your quest, hope ya find something that will work.