One problem related to power steering fluid has been reported for the 2003 GMC Envoy. The most recently reported issues are listed below.
2003 Envoy xl , power steering cooler leaks!!!! constantly putting fluid in resevoir. . There is a current recall for the exact same thing on the 2006 model, but the vehicle is exactly the same from 2003 thru 2006. . . I believe this recall for the 2006 model should include the 2003,2004 and 2005 models also since they are the same part for the vehicles.