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 Models & History. Born as the Toyo Cork Kogyo Co. in 1920, Mazda started out as a machine-tool manufacturing plant but quickly turned to making vehicles. The first Mazda car, called the Mazda-Go, a three-wheeled truck appeared in 1931, which a year later began exporting to China. This was the only car that was in production until the Second World War broke out when Mazda factories began making rifles.