1990 E-350 7.5l 460
I noticed this morning that radiator fluid is dripping onto the passenger side floor. Its leaking from the heater fan under the dash. Any thoughts on where the source of the leak is coming from, and/or how to fix it???

 

Heat core. A small radiator inside the heater box. May be a pita, may be a piece of cake.

Look on your firewall and see where the heater hoses go. Some go through the firewall, but most have the tubes from the core come through the firewall so the clamps are in the engine compartment.

The temporary "fix" is to disconnect the heater hoses and just run a loop to recirculate the coolant.

I had one done on my '86 Ranger and it was about $280 20 years ago, so brace yourself unless you are into diy....