So desert dogs, I'll presume these questions are due to your lack of experience towing.
If I'm wrong, apologies.
You know a 2 ton pin weight is ultimately handled better by a dually, and unless you're already comfortable towing large trailers, it's also my reccomendation as the best way to go.
BUT, that said, a 4000lb pin weight and typical other truck cargo (people and some other stuff) is not out of the realm of the capability of a srw truck. Yes it's heavy, quite heavy, but back to your original question, slap some airbags and some heavy duty tires on it that are good for close to 4000lb ea and you'll drive a lot of miles without issue.
You'll be right at the upper end of your tire and wheel rated capacities but if you think about the 1000s of trucks driving around every day with similar loads, you'll realize it's not the end of the world.
OR, if you want real belt and suspenders, pick up a set of 19.5s, either new, which will run you a couple grand, or keep your eyes peeled for a used set for about 1/2 that.
