2 problems: 1- while driving with no warning the brakes failed. after coasting to a stop i noticed a brake line had ruptured at the frame rail under driver area. i was able to crimp brake line with a pair of vice grip pliers and move truck to a safe location for repair. i believe the brake lines used on these trucks to be of such inferior quality that sudden failure is a common occurrence. 2- my truck has dual tanks for diesel fuel and they have worked sporadically for years. i did not see this as a safety issue as much as an inconvenience. however while my truck was idling on a hot summer day i noticed diesel fuel dripping out of the front tank filler cap. apparently the pump that pumps the fuel from the rear tank to the front tank was receiving a signal to pump even though the front tank was completely filled. it was continuing to pump and leaking the fuel out the filler neck. this seems like a serious safety hazard to me. i do not know if the root of the problem is the float that sticks in the rear tank, the sending units that fail, a wiring ground issue or some other electronic glitch. i do know issues with dual tank duramax diesel trucks are about as common as the truck itself is. after researching online i realized many other owners of my vehicle model have had both of the exact same problems so i thought i should report them.