clanking sound at 55mph

[Anupam Routh]

My 1999 Ford Expedition with 82,000 miles seem struggles when I try to accelerate over 50mph. I can also feel a vibration and a couple of times I heard a loud clanking sound.

When I slow down again, I don't hear the sound. Does anyone have any idea whatthe problem might be?

Thanks on advance for any help.

 

[EddieS'04]

Check the drive shaft U-joints...the front usually causes the most vib and noise at that speed..