bobbondo, I would suggest that your dealer is taking advantage of you, and not servicing your truck properly. Coincidence is one thing, and Murphy was an optimist, but things just don't break ...
I had an Escort that needed the 'top of the engine', also known as the cylinder head replaced. The mechanic took off his glasses, and wasn't Clark Kent any more. He decided he had opened the radiator petcock, and needed to close it. It was already closed, but his super strength was enough to break the plastic 'nut' inside the tank when he turned it.
When I got home, it was leaking coolant on the street. We went round and round to no avail. "Unrelated, these things just happen" on a car with less than 36k.
They broke it, but would not admit it. My alternative was to buy a complete radiator, so I used fishing line and expoxy to wrap the nut, and reinstalled it. It worked til the car was junked 6 years later.
Your 'mechanic' and dealer pocketed a pile of money on your job, and made more than if they got Factory help. And, they didn't do a good job, from what you report.
I'd expect that they got your money once, but you will not be back AND will tell all your friends how "nice" they were to you. Please do that. They will learn that one unsatisfied customer can cause them 20 lost sales, and the opposite is true, after they go out of business.
tom