Exactly at 45 MPH I feel a bit of a vibration on my pedal and floor?

My truck runs great transmission shifts smoothly, but once I get exactly at 45 MPH I feel a bit of a vibration on my pedal and floor. Then it stops if I accelerate more and then when I'm on the freeway I feel it even more and a bit of steering wheel vibration as well as a slight humming sound. I already changed my wheel bearing because I checked it and it did have some play on the passenger side also under the truck I did see that the rubber from my carrier bearing was a bit torn so I replaced that as well. All with Toyota parts from the dealership. I also checked the u-joints and those are in great shape. But the problem still continues. Then I did wheel balancing and tire rotation, and the same thing happened. I did notice that my truck does tend to go to the right side when I'm driving. So, I do now know I need an alignment. Could it be something to do with the suspension or alignment that is causing this weird vibration?