One problem related to defogger has been reported for the 2004 GMC Sierra 2500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 GMC Sierra 2500 based on all problems reported for the 2004 Sierra 2500.
#1. Hvac system with a/c on drivers side ( only) will go into full heat , if you shutoff engine and restart system will be fine again for sometime, there is no set pattern as to when this will happen sometimes a day or a week sometimes a month. #2. Drivers side window will not work , like above sometimes it works fine than it wont work for a few minutes or for a day.
| Windshield problems | |
| Defogger problems | |
| Exterior Rearview Mirror problems |