03 yukon 240000 miles no check engine light no vacuum leaks the front of the engine has a rattle when the heat is on. No oil leaks trans is great coolant level is fine no leak. It took out the blower motor that is fine nothing is stuck anywhere

2003 GMC Yukon 240,000 miles rebuilt transmission very well maintained when I turn on the heat and give the car gas there is a rattle at the front of the engine it almost sounds like a plastic bag blowing in the wind the blower motor is fine there are no vacuum leaks no oil leaks no coolant leaks it only happens when I turn on the heat I'm sure it'll do the same thing when I turn the AC on there is nothing stuck around the fan clutch with the radiator fan there's nothing stuck around the blower motor the blower motor is fine