help please
 

Hey i got a e99 powerstroke 4x4 ex cab short bed and at around 50-55 mph it shakes very bad any ideas on ehat it might be its seems like the whole truck not just one thing particular any info would help:c:

I'd check alignment, wheel balance, and driveline/u-joint play first.

Check the Tracking bar bushings, my 88 would do the exact same thing, very little play will allow it to shake it's self to death.

I checked the drive shaft play n there's none but the front end is really loose n the bar off the pitman ARM i can move it around really easy

Maybe a bent wheel

That's your truck welcoming you to the fun filled world of the Superduty, now get outside and start replacing the steering parts, and while your at it do some ball joints. Then your goo to go for another 100K