78 BRONCO HEATER WHISTLING

[MADMUDDER]

ANYBODY NO WHATS GOING ON IM NEW TO HEAR I WAS WONDERING IF ANYBODY KNOWS WHATS GOING ON MY HEATER IS MAKEING A WHISTLEING SOUND WHEN I TURN ON THE BLOWER SOUNDS LIKE ITS IN THE DUCTS

 

[Krafty]

that would likley be the bearings in your blower fan. if it was the heater core then it would whistle all the time after it warmed up. my f 150 does that sometimes to, but I can also feel vibrations in the dash when it happens, so its defiantly the fan starting to die.

 

[muddrivermike]

Yep thats the blower motor,Mine does it for a while after I turn it on.Im too lazy to change it out.Ill wait until it goes totally.