ED76-551 was born in 1989 by remodeling ED76-514 used on the Hakodate Main Line for the Seikan Tunnel according to ED79. Along with the remodeling, the outer panel painting was changed from red to gray around the lower part of the car body, and the boundary line was renewed to a white belt. At that time, immediately after the opening of the Seikan Tunnel, there was a slight shortage of ED79, so there was a plan to remodel and expand multiple ED76s, but only one 551 was remodeled.

 
After the remodeling, he was transferred to the Seikan Tunnel and was leading the "Hokutosei", "Elm", "Japan Sea", "Kaikyo", and "Hamanasu" in common with the ED79 at the Seikan Tunnel (Tsugaru Kaikyo Line). , ED76 (total length 18.4m) is 4m longer than ED79 (total length 14.3m), so it was necessary to pay attention to the operation such as different stop positions in the station yard, so in later years I concentrated on "Twilight Express" It was used.