2001 Ford F150 Soft high pitch sound

Have you checked the fuel pressure? Especially at first start up?

How do I check the fuel pressure when starting my truck? The gages? (This is new to me). The sound has gotten significantly more noticable too in the last few days and starting up is not a problem, just the higher pitched noise of the engine running and accelerating. Also, I noticed last night that when driving, though smoothly, as I took my foot off gas going 55-60 mph on interstate, that it would paused/delay in down shifting. I figure I just need to take it to the Ford dealership now to get a real take on what is the problem. I just want an opinion before they tell me a novel of what I don't understand since my local mechanics had no clue. Thank you so much.

Ok depending on where the noise is coming from depends on what it is. It could be an alternator or the power steering pump or a/c compressor. If the noise is more underneath or behind you when sitting in the truck, then it could be the fuel pump. You said it don't alway's like to start so that is why I asked about fuel pressure too. Now if you don't feel comfortable doing some checking or testing then take it in and get there diagnosis and then run it through me and I will put it in more laymens terms for you to help you understand what they are saying. Out of question is the check engine light on?

No, there is not a check engine light or anything else lit up to guide me where to go! That is why it is so irritating. The noise sounds like it is in front of me, kinda of on top of everything, if that makes sense. I was watching the RPMs today and it revs loudly mostly when getting up to 2 RPM for each gear it shifts into while speeding up. Then the sound goes away when it goes back down to 1 RPM and in gear. I asked the mechanic about the alternator previously and he said no...and they did a diagnostic and nothing came up. The starting problem went away after my battery was cleaned up so I think that was a seperate issue.
I will probably just have to take it to a dealership since the noise is not getting better and I don't want anything to break down or blow on me. Will let you know what they say and I appreciate you giving me a better idea of what it could be.
Thank you!!!

Ok what you can do is use a long screwdriver or automotive stethiscope and listen to the alternator and a/c compressor and power steering pump. Just simple raise the engine to the 2000 rpm (2 on the tach) and put the screwdriver on the part ie: alt and put the other end on your ear cupped with you hand and listen. Where the noise is the loudest that would be the culprit or possible source of your noise. Tell me what kind of noise is this? Is it a ticking type noise? What engine? and what is the prodution date on the drivers door? I will check TBS's to see if there is any bulletin's on the noise.