Fan clutch finally stuck ON Christmas eve. 123K miles. Temp here in west Michigan was just above freezing @34 F. Started only 1/4 mile after leaving evening services. Temp today was higher 45 F and jet whoosh sound quit after a few miles. Shut off engine for 1/2 hour. Loud sound returned on restart and around town driving. Quit again during a 25 mile afternoon rural drive and was quiet at lower speeds as well. Again engine was shut off for approx. 1.5 hours. Restart and return 25 mile trip after sunset (a little colder) loud whoosh returned and this time did not go away. Found and ordered the better deal you guys mentioned for a new OEM fan clutch on ebay. But , now after reading about AIR pump symtoms in colder weather beginning to wonder if this is related. Like if I had AIR pump problems would that also trigger a fan clutch symptom?