The KM170 automatic transaxle appeared in 1980 models. It uses a torque converter in a fully automatic 3-speed transaxle, including transfer gearing and differential into a compact front wheel drive unit. There are four centers of rotation in the KM170. They are: main center line plus valve body, idler gear center line, transfer shaft center line and differential center line. An aluminum die-cast converter housing and transaxle case are used and the transaxle and differential oil sump is common to both. The torque converter is attached to the crankshaft through a flexible driving plate. Converter cooling is through an oil-to-water cooler, located in the radiator lower tank. The torque converter is a sealed unit and cannot be disassembled.
The 170 series was replaced in 1985, by the 171 series, which incorporates several internal improvements. For service and adjustments, it is vertually identical to the 170. A 172 series transaxle is used in Vista models.