If your 2015 Ford F-250 has a standard 7-way then you can use an adapter like the Pollak Trailer Connector Adapter - 7-Blade Plug to 7-Pole Round Pin # PK12727 to go from the standard 7-pole blade to 7-pole round pin connection type. If you only had a 4-pole connector then you could use the Custer Trailer Connector Adapter - 4-Way Flat to 7-Way Round # KIT-7P-4 instead. view full answer...