Not a 100% sure on the issue but it feels like my tranny is skipping when I'm at a steady cruse doing 60-80. The truck starts to shake quite violently untill you Apply the pedal a bit more or let off compleatly.
Any ideas??

 

That sounds a lot like the problem i had with my 01' 5.4L. My truck would skip and shake between 40 and 60 MPH. I was convinced it was the torque converter or trans. Turns out it was a bad coil pack. I had ford troubleshoot it and they found a miss on the #3 cylinder. They replaced the coil pack and the truck has not had a problem since. If you dont have the equipment to test the truck properly I would just take it to the dealer and pay the flat rate Troubleshooting Fee. Its worth it. I hope this is helpful.

 

I agree with tleach, sounds like a bad coil pack. It should be more noticeable going up a hill in overdrive doing about 60 mph like you said. If your check engine light isn't already on, you should take it out and basically floor until it comes on so you can run the codes to find out which coil it is. Although a slipping tranny isn't out of the question, had that issue with my dad's '98 5.4L, but a flush solved the problem.

 

when my truck acted up the check engine light never came on.

 

my truck is having the same problem! you know how much it was total to get the parts and get it fixed and all?