Whirring Sound Problem with Tranny or Something Else

Hello, everyone. I was wondering if anyone has had this issue. I have a 1996 RMW. I had a problem with the coolant temperature sensor and the gauge read hot although the operating temperature was normal. That day there was also a metallic sound which lasted for less than a minute. It somewhat resembled running over a bunch of coat hangers I was about 90 miles from home, and headed straight home on the highway. When exiting the highway after the 90 miles back, I noticed on the side streets a whirring noise. I assumed it was the tranny.

Brought the car to one tranny shop which of course said I need a new transmission for $2500. Other shops via the phone said it didn't sound like the tranny. Others have agreed with this.

The car shifts fine as far as I can tell. The low pitched whirring occurs when driving around in regular overdrive. If I manually shift in 1st, 2nd and 3rd I don't hear it. The transmission fluid is pink every time I check it. Today I did see a slight silver hue - very little - and upon checking again that was gone.

The car has plenty of power, even through its shifting in overdrive.

I was wondering if anyone has experienced this whirring, and also if the metallic sound could come into play. There is a slight chance that something could have dropped in somewhere as the hood had been open a few minutes before that while we were checking things due to the faulty coolant temperature sensor, so the metallic sound may or may not have been something to consider. It has not made that sound again. It consistently makes the low whirring noise, however.

I'm trying to figure out if this is indeed probably not tranny related, and if not, what it could be. If anyone has any input it would be much appreciated.

sounds like the splines on the sprag are going,.or sunshell is cracked/broken,.

Check everything else first. Exhaust rubbing on body or suspension, power steering pump, accessories up front, cooling fans, AIR pump stuck on, ignition coil on its way out (it will make an audible click everytime it shorts internally). Transmissions are the last thing you want to assume.