The drain for the HVAC system serves both the inside (heater core) box, and any spillover from the outside (evaporator) box.

The vertical part above my hand is the rear edge of the temperature blend door, where objects that fall into the defrost ducts often collect. It's operated by the cable & lever out-of-frame at the top. Many '92-95 trucks were retrofitted with the '96 dual (pull-pull) cable.

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Owner caption December 2012 · Photo 4858 of 5000