Yes they are 37's. If you look close at the 2nd pic you can see the only spot they rub on the radius arm. That pic also was taken to show the suspension flexed and I had another that showed it compressed because someone had asked about rubbing.

I'm not sure what the offset is on the wheels, but they are factory 20" wheels. The truck does have a 2.5" level up front. The rear is stock F350 height.

The Toyo RT is also offered with a 45k mile warranty.

Here is a pic of the size on the tire.

 

You can clear 35's on that truck with a 2" leveling kit with a factory type offset. 9" width and a +12 to +18 mm offset. The truck above is running factory wheels, which keeps the tire/wheel under the truck and allows for a larger tire to still turn up front.

PS sorry he got to your question before this posted. Pretty impressive you have 37's on there with a 2.5" kit. 37's on a Chevy would take about 20 inches of lift LOL

 

Cooper at3 Stock rims 325 65 18s