Det finns ingen officiell bekräftelse, men konsensusen är att titeln hänvisar till "baksätet", 1970-talets samtal för det tredje, ofta dolda säte som ligger i lastbilen på en stationsvagn.
FlickPhilospopher
What does the title mean? It’s a bit of a mystery… but it could refer to the penchant of 14-year-old Duncan (Liam James: 2012, Fred Claus) to escape to the way, way back of the old-fashioned station wagon, to the seat that faces backward out the rear of the car, to not have to cope with his family. (This scenario opens the film, and the film will return to it, poignantly, in the end.)
The title refers to the rear-facing back seat of a vintage station wagon
IMDB Trivia (så obekräftad)
The script was written in 2007 as "The Way Back", but the title was later changed to avoid confusion with the film The Way Back (2010). The title refers to the "way back seat," the 1970s colloquial expression for the third, often-hidden seat located in the cargo section of a station wagon.