One problem related to blower has been reported for the 2003 GMC Sierra 1500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 GMC Sierra 1500 based on all problems reported for the 2003 Sierra 1500.
Hvac system will hang up on defrost, it will not return to any other position until vehicle is restarted with switch in different position. Also when using vent on the higher fan settings you can hear and feel a surging of air the fan is not a producing a constant flow of air.