Other Fuel System Tank Assembly problems of the 2006 Chevrolet Silverado 2500

We brought our 2006 Chevrolet silverado with around 73,000 miles on it to a repair shop for a tune up and we were told the following: “the fuel lines are very rusted (starting to seep back by the tank area) the brake lines are very rusted, the truck will need rear brakes very soon, all brake hoses will need to be replaced, the bleeders on calipers are rusted out, the shimmy shock in the front end is blown apart, has a lot of play in the idler arm, front shocks rusted & leaking, rear shocks rusted, rear end cover rusted, the transfer case tail shaft is leaking, the frame is rusted & getting thin in spots, has at least three broken exhaust manifold studs� we understand that brake pads and calipers are usual repairs and maintenance. However, the vehicle is only six years old and the truck should not be very rusted. We called Chevrolet and opened a case to review the rust issues. We brought the truck to a dealership as requested by Chevrolet for a visual inspection. Using document id #2758961, the technicians determined “no repair or consideration should be given for this concern - surface corrosion on unprotected components will vary with age and exposure. Corrosion on these components will vary with age and exposure. Corrosion on these components has no detrimental impacts, either in short or long term durability. " however, they explained that if they were us, they would replace the brake and fuel lines. The Chevrolet case worker called the dealer and confirmed the findings. He explained to us that the rust was due to environmental factors and normal wear and tear. We tried to get a definition of environmental factors, however the worker would not explain further. . The truck resides in the north east; it is subjected, as all vehicles are, to many environmental factors every day.