Automatic Transmission/Transaxle Cooler and Lines Flushing Procedure: Automatic Transaxle/Transmission (A/T) oil cooler and lines must be power flushed completely before an overhauled or replacement A/T is installed (except SKYACTIV-DRIVE). The most common cause of repeat A/T failures is lack of lubrication to the front and rear planetary gears. This is usually caused by an accumulation of metal particles and debris (from a previous A/T failure) on the internal mesh type baffle of the oil cooler. Power flushing will remove the restriction by back flushing, followed by forward flushing to dislodge a restriction, then back flushing again. This will in turn ensure full ATF flow for the transmission when it is operating.
