hadn't driven my truck in a little while so mom had been using it and when i drove it to work to find a oil leak the other day i noticed a small rush of air through the heater core after stepping on it, upon looking for the oil leak today (blown valve cover gasket) i noticed a funny looking object on one of the exhaust runners and when i picked it up i found it to be a snapped head stud (2nd back exhaust side) i installed the hasley studs 4-5 years ago when i did the head gasket to kill the 300k mile front corner coolant leak and really don't want to pop $475 for a new set of studs if i don't need to