I got a '92 f150 and for a couple of months the fan has been making some racket. It started off just being on warm up then it would run normally but since about a week ago it was loud all the time. Now this morning I lost low, 2 and 3 levels but high still works but it is so loud that I have to turn my stereo almost all the way up to hear the radio!

Is this a blower problem and/or a resister problem?

Its tough up here in MN without defrost!

 

Your resistor is toast, and the blower fan might have bad bearings in it or at least debris caught in the fan blades to cause the noise.