Yeah, if you bought crappy tires, with bad carcasses then they'll be tough to balance, but once again, I maintain it's a driveline issue, not a tire or rim issue. If you can drive out of it, it's not likely to be a tire. Pinion angle usually causes low-speed vibrations that can be driven through.
I guess I shouldn't irrefutably say "it's not tires" but I would be looking very hard elsewhere before I condemned tires. I also don't cheap out on tires, but I spent a few years as a retreader, building tires before I became a mechanic. You also kinda hinted towards what I was saying. I said it's not going to be brakes, or steering components, but likely driveline. Steering/suspension tends to come in at a certain speed and then not go away until you're nearly stopped. Tires tend to start around 80km/h and go away when you drop back below that speed, and get worse as speed increases. Driveline vibrations are typically at lower speeds and can be driven through, that is to say they start at a certain speed and then go away above that.
What I'm trying to say is that there is no reason for there to be incurable vibrations, if you're willing to spend the time to diagnose them and replace the parts causing the problem. If you have a poorly installed lift that has your pinion angle out of whack, that'll cause a vibration and the only way to correct it is to correct the pinion angle. If you have a vibration from cheap, poorly constructed tires, the only way to fix it is to buy better tires. If you have a vibration from running unbalanced, offroad rims, see above. None of it is incurable, you just need to have someone diagnose it properly.
I had a guy argue with me for a month, and 4 different visits to our shop that his lift blocks were installed backwards and were causing his low-speed vibration. His pinion angle was about 4* off from the output of the transmission. I flipped his blocks around, got the angles to within .5* (spec for any u-joint drive shaft), and lo and behold, his vibration went away. If you've lifted your truck with an add-a-leaf or anything, that would be the first place I'd check. I've never seen your truck in pictures or in person, but I've dealt with a lot of lifted trucks in my career and I can tell you that none of them had a consistent vibration at 40mph that goes away after that.
ETA: Also, if you're still on your same set of tires from 2011, they're nearing the end of their life cycle, so they will be getting harder and harder to balance as the carcass begins to fail.