One problem related to brake fluid leak has been reported for the 2003 Chevrolet C1500. The most recently reported issues are listed below.
Driving south on garden state parkway new jersey, stopped to get NJ numbers, truck stopped fine. Upon getting back into truck placed in reverse stepped on brake, right to the floor, no warning, no lights, nothing. Went back into store bought some brake fluid filled reservoir pumped brakes back up and did get some pedal. Upon starting truck applied brakes, right to the floor. Checked under truck, fluid leaking from rear, appeared to be from above the pumpkin. Upon having the truck towed home approx 30 miles, next day checked under vehicle, brake line rusted right through, leaking all of extra fluid out onto pumpkin. I do believe if I had been traveling north on the parkway at speeds of 65mph and had to hit the brakes in any emergency situation, the aftermath could have been fatal for someone. I have been driving for 50 years and have never had a brake line rust through and pop with out any warning, very dangerous problem. The brake lines are majorily flawed, such a high pressure system should be stainless steel, not some cheap steel that could have proven fatal. Thank u for listening.