# The oil ageing index The oil ageing index is part of the operating data and provides information on the current quality of the transmission oil. The oil ageing index must be deleted after every oil change. For further information, please see: Reset (Delete) and Oil change support.
| The oil ageing index is still under development in the transmission software version D5.2.0.0.
| Further topics:
More information on: Reset functions More information on: Oil change support More information on: Operating data More information on: FAQ Up > Higher-level section © by Voith Turbo GmbH & Co. KG send remarks to joachim.ehleiter@voith.com (electronic department) or r.theilacker@voith.com (electronic department)