2011 Chevrolet Silverado 1500 suspension problems

My front driver side top control arm broke when I hit a pole on the rear of my truck. It snapped off at the ball. I was in a parking lot and side swiped a pole at about 5 MPH. Should not have snapped a part in the front of the truck! There is a massive amount of corrosion under my truck. Even behind the rear tail light which shouldn't have been exposed, there's rust. This truck has more rust that trucks that are 30 years old.

Tl* the contact owns a 2011 chevrolet silverado 1500. The contact stated when he put the vehicle in gear it made a very loud clanging sound. The vehicle was taken to a dealer for diagnostic testing and was told that was normal since all of the new GM vehicles made that noise. The failure recurred repeatedly became progressively worse over time. The contact also stated that the frame and suspension had extensive rust on it. The dealer advised the contact that the rust was not a problem.