Headlights are dim on my 07 f250 powerstroke. Have to leave them on bright to see good. On coming drivers do not flash me to dim lights. took to ford house, alternator and batteries putting out normal power. Any suggestions please?

 

Unless someone has had this exact same problem, this is what I would do.
Get a voltmeter and confirm that you have the full battery voltage available at the headlamps. If OK, then confirm that the ground connections for the headlamps are good.
If both of those two items are ok then consider replacing one headlamp bulb and see what results you get.
If the results of the previous tests are not up to par, go after the voltage supply starting from the battery on to the fuse panel then to the relays that supply the headlamps.

 

...and check all your ground connections.