My truck is a 96 f150 I have a vibration that comes and goes as I am driving 40 mph and up goes from rattle your teeth out to perfectly fine just did a clutch I have checked and rechecked all bolts and drive shaft any help would be much appreciated.

 

Did you replace the pilot bearing, or atleast check the old one, when you did the clutch? I'm not sure if this would cause your problem though, just a thought.

 

Yes I did replace it and the truck only has 70000 original on it.

 

Intermittent vibrations can also be U-joints. Given that you just replaced your clutch it could also be clutch related. You may have to take is all apart again to see if there are any issues with the new parts.