Jeep Grand Cherokee Dual Control Blend door Fix (98-04) - Heat and AC Blend Door Replacement Parts
The HeaterTreater Pro is configured to maintain dual HVAC control in a Jeep Grand Cherokee Limited. The kit includes two axles compatible with the GC blend door motors for separate control of driver's side and passenger side temperature.
Installation of the HeaterTreater PRO requires removal of the heater box. If your plans already include replacing the heater core or AC evaporator, the additional work to replace the blend doors with HeaterTreater metal components is minimal.
Removing the Heater box is an involved process requiring the following steps: 1. removal of steering wheel and steering column. 2. removal of entire dash panel. 3. evacuating and disconnecting AC compressor 4. drain and remove heater hoses going into driver's compartment. 5. complete removal of heater box. re-charge AC system(note EPA certification required). 6. re-assembly of all components.
The process takes about 8-12hrs and automotive technician level skills. The pictures show how the HeaterTreater is configured for dual control. The stability of the system has been thoroughly checked, and it will function flawlessly. Note that all moving components are metal and will not be susceptible to the same wear out mechanism as factory replacement components.  The HeaterTreater Pro has limit pins on both the passenger and driver’s side axles.  This both provides the correct limits of door operation without placing undue stress on the doors and provides lateral stability to insure that the doors do not shift and scrape on the sides of the box.  This is critical to long term reliable operation and is not an element of competitive products.
The HeaterTreater PRO is also available as a reduced price kit including the HeaterTreater Re-circ door fix. As long as you have it completely apart, you should consider replacing all doors and the heater core, and maybe the evaporator. It's a lot of work to do twice.
