I have a 2005 f350 diesel, standard cab, 8ft bed, the front 2 bed mounts that support the bed, that go between the bed and the frame rusted and collapsed, so now the bed sags foward towards the cab, I'm not sure where to start on fixing this, I don't know what these "bed mount" pieces are actually called, or where to get them, any help would be great! Thank you!

 

Those would be the bed crossmembers, and you need to pull the bed off and have new ones welded in place.

 

Is it just steel, or do I get specific pieces