I have an '08 Silverado crew cab with manual HVAC controls. I have visually verified that the temp actuator is faulty. (I can see the actuator on top of the HVAC unit between the radio and passenger center dash vent.) Is there a way to replace this actuator without removing the whole HVAC system.

 

Well after a few hours (and cold ones), I began to examine the passenger side dash. after removing the upper glove box I found four 10mm screws retaining the passenger airbag. after carefully unplugging the safety pin and plug the airbag was able to be removed easily. from there i was able to gain sufficient acces to the temp actuator to replace it. I have now determined that the Heater A/C control box is not fully working. I have ordered a new box in hopes that this will finally solve the issue.

Please note that EXTREME care was taken while disconnecting and re-connecting the airbag!!! Once I visually placed my hands on both sides of the plug I moved my head BELOW the dash to protect myself in case of deployment.