Expire is not really the right term; but effectively yes. In general a cheque older than six months will be considered stale-dated and will not be honoured. Reference the Canadian Payments Association FAQ.
SKYACTIV is a brand name for a series of technologies developed by Mazda which increase fuel efficiency and engine output. The initial announcement of the SKYACTIV technologies include new engines, transmissions, body, and chassis, which appeared in Mazda products from 2011.
Mazda North American Operations. Mazda North American Operations (MNAO), which includes Mazda Motor of America, Inc., is Mazda Motor Corporation's North American arm, and constitutes the largest component of that company outside Japan. The company has its headquarters in Irvine, California and is headed by Masahiro Moro.