You need the Whine-O-Meter, its right beside the board stretchers at your local hardware store
All joking aside, keep driving it to the point that it pisses you off so much you go into the dealership angry. AND don't leave there until you have an answer on how they are going to fix it. This is the important part. You won't take no for an answer, you won't take, "we've done all we can do" for an answer, you won't take any answer other then, "We'll get your truck fixed right".
You must be royally pissed off, with a get out of my way attitude. Ask for the service manager if you have to. And most importantly be respectful. This isn't personal, you say and do all the right things but you be as big of pain in the ass that you can be.
People don't care about you, your truck, or whether or not it whines. You want change, you have to make the change happen.