One problem related to brake fluid leak has been reported for the 2003 Chevrolet C/k 2500. The most recently reported issues are listed below.
Steel brake line to rear of truck rusted through, which caused brake fluid to leak out & system could not generate sufficient pressure to stop the vehicle quickly. Fortunately traffic was relatively light and I had a significant gap in front of me. The brakes functioned normally several times prior in the same trip, and no warning light came on, even during the failure. At the next key off & on, the warning light did actually come on.