i have an 87 2wd dakota, i get this vibration at around 40 to 45, it feels like it is in the front end . sometimes more severe than others. i have put the truck in nuetral when this happens and it is still there. i have tightened the wheel bearings, ujoints seem fine, a little play in the inner tie rod but not alot. carrier bearing is new. anyone have any ideas, thanks.

 

Check the two big bolts that attach the rack to the frame. They have been known to tear away from the frame.

 

You should also check all your bushings for the control arms too.