Two problems related to brake fluid leak have been reported for the 2003 GMC C2500. The most recently reported issues are listed below.
During a tire rotation at costco , they discovered brake fluid leaking from the brake lines. Upon a further investigation ,the brake lines are leaking and found to be rusted out. I have been using the vehicle to tow a 2010 air stream and thank god no accident or injury has occurred.
Applied brakes brake light came on along with brake system service needed lost pressure on pedal and all lost fluid still had small amount of braking (brake lines corroded and leaked out fluid ,lines should have been made from stainless steel not cheap steel. ).