If no one still knows what it's from, feel free to start a new round since it's been over a week.
There really aren't many other hints to give, apart from character names etc... So, it's adapted from an American TV series, the setting is America, the characters are Americans, the car is American... The main characters' family is named after an old American firearms maker.
The studio was Madhouse, MCs' voice actors for the dub were the original actors Jensen Ackles (only in the last 2 episodes though) and Jared Padalecki. Oh and the whole thing is named after a frickin' genre.
Failure said he'll post a new one later, so I'll just reveal the answer then.