Used vehicle sales, excluding minivehicles, fell 8.6 percent in July from a year earlier to 396,057 units, down for the fourth straight month, an industry body said Thursday.
The Japan Automobile Dealers Association said the decline may be a result of the surge in gasoline prices that has made consumers refrain from buying vehicles.
There were also more people buying new minicars with better fuel efficiency but with prices equivalent to those for used subcompacts, it said.
By type, sales of used cars with engines larger than 2,000cc declined 6.4 percent to 156,969 vehicles, while sales of cars with smaller engines shrank 12.4 percent to 176,751 vehicles.
Sales of used trucks dipped 0.5 percent to 50,191 vehicles, but bus sales rose 5.9 percent to 1,788.