I have pretty annoying chirping/squeaking when I turn on the heater/a/c fan on my 86 cougar. I'm wonder if anybody has the same prob, and an answer to fix or quiet/smooth down that squeal
I had one in my '84 LTD that did that (fox chassis also). I ended up having to replace the heater box becaue I'd broken the other one. In the process I replaced the fan that came with the "new" housing so that solved the problem.
It may just be debris in the fan. Take it out and you'll find some I 'm sure.