Ford C6 Transmission whining when hot and losing gears

Ford C6 Transmission whining when hot and losing gears
No issues when cold. Drives through all the gears just fine.

[@WorksforMe]

It turned out to be a lot of crud in the transmission pan which blocked the oil pump pick-up. The oil pump was starved of oil and thats what made all this noise. After cleaning the pan and changing the filter this issue was resolved, at least temporarily

[@MattsRageFitGarage]

My truck has made a similar noise for years when warm but I can only hear it from outside when its in park. Trans has always worked fine but its got 253,000 miles on it. C6 also. About to rebuild it soon when I put my new engine in. I figured it was the trans pump making a slight whine noise but it kind of resonates along the bottom of the truck, could never find anything else under there that could vibrate and make that sound either.

[@WorksforMe]

In my case, the pump was whining because it was starved of oil. The pick up tube was clogged with junk. The transmission is working fine now after an oil change.