I picked transmission thread, because, well, I think it could be related, but honestly I don't know.

Wife (who almost exclusively drives truck) reports a whine type noise can be heard from the drivers seat. I had initially thought might be P. Steering pump. Once I actually hear it...and it takes a while to catch it as it's not that loud...I can't replicate or change the whine with steering wheel input, so I'm thinking to exclude that. From under the hood I can't hear it there either.

I can hear it in park, at idle, and can modulate it with gentle pressure on accelerator. Once the engine revs too far, I lose the noise due to engine noise.

Also, as identified in another thread, there is a bit of a shudder when the trans kicks down or goes from limited to full lockup(if I'm describing that correctly?), usually at highway speeds, but not exclusive to high speed. I doubt it's plugs as they were done with COPs, so lets bypass suggestions about plugs for the moment.

Thoughts on these two, possibly related scenario's? My wife in in panic mode...

I have no idea which tranny is in this truck. '00, 5.4L, 4x4 if that helps.

 

My 2000 F150Scab 5.4L 4x4 had a 4R70W. If you can barely hear it, I wouldn't worry too much. If it's serious, it will get worse. My truck makes a little whining noise too and I don't worry about it.

Get the transmission code off the door sticker and look it up. Google for Ford transmission codes. That code will tell you what it came with.

 

Alternator bearing failure? Remove serpentine belt and try to duplicate the noise.

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That's a good possibility. I've had that problem before on a 302 V8 70 Mustang. Heard a whining noise only when I first put in in gear, reverse or drive. After accelerating a little, it went away. An experienced mechanic diagnosed it with a long screwdriver. I and all of the other mechanics at the Ford Dealer shop were convinced it was the transmission. They removed the alternator belt and the noise went away. The car had a 50k miles drive train warranty. That knowledgeable mechanic saved Ford the cost of a transmission rebuild. Eventually, the alternator failed and I replaced it eliminating the problem.