Planetary Gear Trains

WARNING: This page is about a different variant/trim than selected.

The 8 forward gears and the reverse gear are produced by a combination of four simple planetary gear sets, three clutches, one brake and a launch clutch. The front two gear sets share a common sun gear. Power is output always through the planetary carrier of the fourth gearset.

The 5 shift elements comprising 3 clutches, one brake and a launch clutch, are responsible for all 8 forward and reverse gears. High efficiency is achieved by the use of only two shift elements disengaged in each gear which reduces drag.

Over Temperature Messages

The transmission clutch temperatures are modelled within the TCM . The 8P75XPH transmission incorporates additional monitoring of the B clutch as this is worked hard on low speed crawl situations. The TCM uses algorithms to detect high load on the launch clutch and when detected provides a message to the driver to select low range. Further monitoring then provides a critical warning to the driver with a notification sound from the instrument cluster to select low range if this first message is ignored.