May has been a bad month

Well it starts like this,brought my truck in for routine oil change and mentioned that i had a coolant leak some where had it spray all over my engine cover.
They came back said all levels were normal so i left.
came back a half hour later showed them the coolant leaking they said i needed a radiator cap which they didnt have in stock had to order.I left for 2 days still leaking anti came back had cap installed and left.
Came back still leaking had radiator replaced. Then on mothers day on our way to dinner on the expressway transmission went out trans fluid everywhere whole bottom of the truck coated in it. Returned to dealer again trans lines to the new radiator cut and leaking,They replaced trans lines.

This past weekend tried to launch my boat for the season, accelerating while towing i get this loud groan and vibration,also does it even worse when not towing accelerating form any speed hitting passing gear.

Got a call from the dealer today saying that it is the muffler, I've never heard something so ridiculous in my life i even had the so called mech with me and let him hear it for himself.

Long story short ive just about had it with this truck.

I'll let you guys know if the muffler fixes my transmission