Yeah, another tire question

This link will tell you the difference in width etc of the two tires which you can see how much of a difference there is..

https://www.tacomaworld.com/tirecalc?tires=255-80r17-235-80r17

Height may not be a problem but width may be. Check the clearance between the tires on the duals. You do not want those "kissing" or real close when fully loaded. It will cause early tire failure.

I had 255 80 r17s on my Ram 3500 and when the camper was loaded the sidewalls would touch. Don't run it or use spacers

GM has always used narrow 6.5" wheels. Just be aware mounting a tire with a 7.5"+ wide tread on a 6.5" wide wheel can have the tire riding the center of the tread especially when pumped to those high pressures needed for carrying a load.
Load carrying tires work at their best when the tires tread matched the wheels width unlike a vehicle that doesn't carry heavy loads ie; race cars...drag cars...off road vehicles/etc.

Get with a experienced truck tire dealer that sells lots of tires to LDT owners. Good ones can give you pointers on load carrying tire/wheel tech.

I've been running Nitto Dura Grappler on my '06 F350 dually for several years. Outstanding highway tire with very strong sidewall for carrying typical camper loads. It's not as aggressive of a tread as what you're looking at, but unless you're slinging a lot of mud or snow you're just making more road noise and they'll wear out faster. Here in the West we're on gravel and just unimproved forest or desert roads a lot, the Dura does just fine. Oh, and did I mention they make em in your size!

Did you consider BFG KO2 AT? Similar tread pattern, stiff sidewall and great traction. They come in stock size. I've had mine about a year now and am very happy with them.