I have a 2001 Ford Expedition. It has the big 8 cylinder engine. A few seconds after I start it, it makes a loud sound under the hood and lasts for about 5 to 10 seconds. Seems to happen when the engine is cold. Any ideas?
You will hear some noise if extrememly cold outside as the oil hasn't had time to circulate and is thicker than normal.
However I recommend regular oil changes at 3,000 miles, using 5w20 motor oil and using factory oil filters as we have seen some issues with the aftermarket filters not holding lube oil and causing the engine to actually run dry for a few seconds like this.