I have an '01 F-150 with 80,000 miles on it and now when I'm at about 60mph or above I feel a slight viberation through the steering wheel and a loud humming sound, also when I'm at say 70mph and my RPMs are at 2000 and I let my foot off the gas the RPMs and speed will slowly move down, instead of my RPMs dropping quickly like they should. Its almost like the torque converter is get stuck, also in 1st gear when I start out I hear a clicking noise, and when I'm slowing down and I will hear it after I have been on the freeway for a while and slow down and it shifts down into first gear.

Its always hard to describe things in words sometime, but I hope someone can understand this

 

Slide under your truck and grab the yoke(the part of the driveshaft closest to the tranny)and check for play.It sounds like your d/shaft is out of balance and wearing the extension housing bushing .Theres a tsb on it , I have an 01 screw and was told by the dealer that it didnt apply to me.But it did,I replaced the stock d/shaft and put a new bushing in the housing and no longer have that problem.

 

I checked the front yoke on the driveshaft and when I turn it back and forth (grabbing the yoke only) it does turn back and forth a bit maybe 1/4 of an inch

 

My Question Is Below

 

HEY ganiman ,I HAVE A QUESTION FOR YA
I HAVE A '01 SUPERCAB F150 ,MINE DOES HAS SLIGHT MOVEMENT UP & DOWN .IS THE SHAFT YOKE IN TRANNY SUPPOSE TO HAVE >ANY MOVEMENT< UP & DOWN/SIDE TO SIDE???