Japan's of cars, trucks and buses in October rose 18 % from a year to 500,004 units, a record for the month, the Japan Automobile Dealers ' said.
The strong growth followed year-to-year increases of 21 % in August and 12 % in September.
The monthly sales have been setting records every month since March.
October sales, compared with the previous month, inched down 0.4 %.
Sales of passenger cars grew 22 % from a year to 361,376 units.
Sales of medium-sized cars, which benefited from price reductions arising from introduction of the consumption tax, more than doubled to 30,841 units from 13,056 in October 1988.