my dad has a 06 dodge 2500 with a 5.9 cummins and when he starts it up the head lights go bright then dim and then the get bright again and dim and they keep repeating that process for like 10 mins and it stops... does anyone have that problem?

 

Guessing you live in a colder climate, its the Grid heaters cycling, they draw like 195Amps if I remember right.

 

Not a problem. It is the grid heaters cycling...