I have tried everything on my 1996 f250 7.3L nothing seems to help. it starts right up but idles real rough and if you hold the throttle to the floor it will gradually pick up rpmbut when driving it dosent have enough power to get out of third gear. i need help

 

1994.5 - 1997 7.3L Power Stroke Diesel - Ford Truck Enthusiasts Forums Here is a link to the Power Stroke page, probably better to post your problem there for specialist help.
Good luck.