My 97 Ram van 3500's heater core is bad, i'm planning on replacing it myself. I have already practiced on a scrap van and know how to remove it and replace it. I just need to know the OEM part number or the aftermarket part number. I have found a few online but I want to make sure I get the right one. I've tried looking for the service manual online to figure it out but i'm not feeling like forking over $80 just to find a part number.

 

Just a swag: https://www.moparpartsgiant.com/part...~55036425.html
Rockauto seems to agree for vans with heat/AC. Might be a different part for heat only. (Rockauto may be confused about the front heater.)
The manual only shows the one style and says the evaporator is simply omitted for no A/C vans.
You can see the heater hose connections at the top corner of the heater/evap box.