Those are adapters yes, but the inside pattern I'd guess is 8 lug on 6.5" as found on 3/4 and 1 tons. So if that's what you have it could work, although that large and heavy of a tire will make your 3/4 or 1 ton brakes feel very weak.
If you know what bolt pattern you have there may be other options. However I suspect that anything larger than the 8 lug pickup pattern and not already the full size 10 lug semi truck pattern is a no go.
One decent option is Dayton wheels/hubs will accept super singles and tubeless rims without any adapting, so long as the likely larger tires/wheels fit the rest of the truck.
Grigg
