SO i have just under 29k on my ram. now that winter is here, i am using my heater (fan) more. most of the time i have no problems, but as of late i get a growl that goes away after a few min, or if i cycle the fan. im taking it in to the dealer on monday, but. is it easy to replace if i had to do it? i now its not the blend door of death issue, but has anyone else had issues with the Blower motors?