I have a 2001 Ford F250 4x4 with 150k miles. The other day, after I had been driving for about 2 hrs. I stopped at a convenience store and when I came out the truck wouldn’t turn over. I opened the hood and the starter solenoid was so hot I couldn’t touch it. After it cooled off for about 1/2 hr, it started right up. After that when I started it I got a sound that was somewhere between something hitting the fan and glass being ground up but with more of a metallic sound. I replaced the starter solenoid thinking the problem was that the starter wasn’t disengaging. That didn’t fix it. The truck starts right up but the noise is so disturbing I turn it right back off. Please help.
Assuming you can hear it when the car is at idle, get a length of garden hose and use it like a stethoscope to locate the source of the noise. Without a better description I can only think that you may have a bearing on one or another pulleys for the accessory belt.
Study the serpentine belt then remove it. Start the engine. Is the noise gone? If so, turn each pulley in the belt system by hand until you find the failed bearing…Replace whatever failed…