This Carhartt shirt is distinguishable from Dean’s S4 blue Carhartt shirt by the fact that the breast pockets have flaps. It’s a rich blue shirt with cats-eye coloured buttons.
In Out with the Old (7x16), Dean wears this shirt for the entire episode, except for when he wears a suit to investigate the case (he changes out of the suit after retrieving the cursed gentleman’s magazine.)
In Sharp Teeth (9x12), this might be the shirt that Dean is wearing when he attends the prayer group at Garth’s in-law’s house. He wears it until the evil werewolves are killed.
In The Vessel (11x14), Dean wears this shirt until he has to steal and wear a navel uniform in order to blend in on the submarine.
In Patience (13x03), this MIGHT be the shirt that Dean is wearing when he hears about Missouri’s death at the gas-station. He wears it until the end of the episode.
Fate: Presumably, this MUST get left behind on the submarine in The Vessel (11x14). Unless Dean stuff it under his stolen navel uniform somehow.