2002 GMC Envoy. 2003 GMC Envoy. 2004 GMC Envoy. 2005 GMC Envoy. Vacuum Closes Non-Bypass Heater Valve. Heater Valve. Type: Heater Valves. Ensure that this part fits your vehicle by entering your vehicle's Year, Make, Model, Trim, and Engine in the Compatibility Table.
