The HeaterTreater replaces any of the plastic doors in the Dodge Ram HVAC system with steel. Replacing the existing doors with another plastic door is at best a stop-gap solution. The failure is a result of excessive forces generated by the DC servo motor in the calibration of the door.
There are four different door systems in the truck and HeaterTreater can replace any or all of the doors.
1. Re-circulation door.
This door is located above the fan motor behind the glove box opening. You can observe the door by fully opening the glove box and checking the door through the internal air intake grate. When broken, it can either stall in one position or fall down on top of the fan motor. It should be either fully open or fully closed, never in the middle.
The RAM has a design flaw and a stop point molded into the re-circ box is missing such that force is always applied to the door in one direction, not the limit pin as designed. This door is most susceptible to failure and replacing it with plastic will ultimately fail again. The dealer sells a complete new box with the molding error fixed, but you have to remove the plenum box and evacuate the AC to access it. Even after all the work and with re-designed parts, the cheap plastic will still fail again. Our steel door takes into account the Dodge design error and is a permanent fix.
2. Blend door
The truck has an upper and lower blend door that "clamshell" over the heater core which is on a horizontal plane. The upper door is connected to the actuator motor and has to withstand the calibration forces and is susceptible to breakage. The lower door is connected to the upper door with a wire rod and is strictly a follower to the upper door. Typically we see the upper door break and our blend door listing ships only that door and just re-use the lower plastic door since it is primarily flow control, not temperature. We can replace the lower door if there is physical damage to the lower door, just contact us via email (firstname.lastname@example.org) and we will provide parts and additional instructions.
The above discussion is for single control, not dual control(separate temperature control for driver and passenger). On the dual control system there is an actuator motor hidden on the back of the box to control the passenger side blend doors. We can replace the upper and lower doors, but this will convert the system from dual control to single control and again, we need email notification that it is a dual system. Note that failure on the dual control system is rare and generally we recommend leaving it alone unless there is obvious physical damage. May be a different control algorithm or stronger parts, but failure is rare.
We do see issues with a temperature differential between the driver and passenger side on both dual and single control that is related to problems with the heater core and/or the AC evaporator core. If you can change temperature, but not get good performance, the core(s) are probably the problem. We have write up's on both issues and will be happy to provide additional information via an email request.
3. Mode 1 door
There are two mode doors that control the direction of air flow. The mode 1 door cuts the dash vents on and off, and when off air is diverted down to the mode 2 door which switches between floor and defrost. The most common symptom of a bad mode 1 door is for the truck to be stuck on dash air with no floor or defrost. This is a safety issue if you encounter ice or snow and should be fixed. The video linked below shows this door being replaced.
4. Mode 2 door
This door will switch between floor and defrost when the dash vents are off. The most common failure is to be stuck on defrost with no floor. In some areas of the country this may not be a big problem but we get complaints from guys pushing snow plows in Minnesota that can't live with cold feet!!! We recommend replacing both mode doors if either is broken.
On the four door mega-cab there may be an additional door connected to the mode 2 door that controls the amount of air flow to the back seat. It's kind of a goofy design and will cut off air to the back seat when if max defrost mode. That would be useful if climbing Mt. Everest in a blizzard but just cutting up the fan flow will generally suffice. The back seat flow is poorly designed and always breaks. The dealer solution is to replace the entire lower box, but this is at best a temporary fix. We replace the mode 2 door and just block the rear seat vent about 1/4 open or any position up to blocking rear air dependent on useage of the truck. This is how trucks were configured for years and the added functionality is problematic on the later trucks, and its best to just eliminate it.
Aluminum vs Steel air doors
We are the industry engineering experts on air doors and have been in business over ten years with multiple vehicle application. Early on we evaluated aluminum doors and found some obvious and not so obvious issues.
- Aluminum would appear to be lighter and less stressful on the actuator motor...not true. As we all learned in Kindergarten physics, if you have a fat guy sitting in the center of the see-saw, it doesn't have an impact. Rotational stress is a function of distance from the axis. Our doors are heavier, but the bulk of the weight is in the axle which has no impact on required torque. In fact, the added axle weight actually stabilizes movement.
- The actuator motors have waaaay more torque capacity than required for this application, and actually is the root cause of the common failures. We've been doing this across multiple models and have never seen an issue with motors wearing out or breaking with steel doors.
- Welding aluminum plate is problematic and we saw issues early on with doors breaking at the periphery of the weld pattern. Aluminum plate changes physical characteristics from the extreme heat associated with welding and becomes weaker at the weld point. This is why aluminum plate is riveted, not welded on airplanes. Welding is OK on aluminum structural components that can withstand the heat, but not plate.
- Aluminum is "springier" than plastic and can vibrate in the air flow producing a humming noise. It's generally not an issue or even annoying, but the resonant vibration can further weaken aluminum welds.
- Our steel plate is more rigid and gives a more reliable and consistent seal against the extents of movement.
The standard Dodge dealer fix for the door failure is to remove the plenum box and replace which ever door is failing. Removal of the box requires removing the dash panel, removing steering wheel and steering column, evacuating and disconnecting the AC compressor, draining and disconnecting the heater hoses. Fixing the door is relatively easy, but the labor(and cost) of getting to the door makes this a time consuming and expensive job.
The Heater Treater avoids the hard work by providing a kit that allows the repair to be done with superior components without having to disassemble the automobile. 1-2 hours work vs 8-14 hours of work, and no specialized mechanical skills or tools required.
The 2002 Ram was a changeover year. If you have an ’02 you should check this listing and the ’95-’02 listing to see which system you have.
Do you have the problem?
The Dodge Ram Pick up Truck has four separate doors that can all fail independently of each other. Due to poor design, the failure of each door is inevitable and we recommend you replace all of them rather than having to do the same fix multiple times. Heater Treater offers special discounts for purchasing more than one repair kit at a time. We sell the first door at $119.92 which covers overhead and margin and additional doors at $45ea.
The following videos take you through the process of diagnosing which doors are broken and how to fix them. Once you have the Heater Treater system, repairing the doors takes less than an hour and can be done by anyone regardless of mechanical experience.
Choosing Your Solution
To purchase, select how many doors and of which type you need above. You can also read a more detailed description (opens new window) to determine which doors you need.