Overview
This document contains information on:
General
Function requirements
Function
General
The oil supply system is responsible for the lubrication of all the relevant components in the dual-clutch transmission.
Function requirements
Engine management ON (circuit 87M)
Engine in operation
Function
Dual-clutch transmission oil supply
The oil supply, lubrication and cooling of the dual clutch transmission is performed by the following procedures or components:
Two oil pumps operating independently of each other, i.e. oil pump (primary pump) and an electric auxiliary oil pump or a pump dual clutch oil cooling system
Centrifugal oil lubrication running through gears in oil bath
The following dual-clutch transmission components require a constant supply of oil when in operation:
Fully integrated transmission control electrohydraulic controller unit
Gear sets and shafts as well as all moving component parts on dual-clutch transmission
Dual clutch
Gearshift actuator
The following types of oil supply are available:
Oil supply through centrifugal oil lubrication
Oil supply through dry sump lubrication
Oil supply through oil pump (primary pump)
Oil supply through electric auxiliary oil pump
Oil supply through dual clutch oil cooling system pump
Centrifugal oil lubrication
The transmission oil is spun-on in the dual-clutch transmission's gear sets rotating in the oil sump or forwarded to the engaged fixed or idler gears. The spun-on transmission oil is responsible for most of the gear set and bearing lubrication.
Dry-sump lubrication
The oil is delivered into the air intake chamber from the gear set chamber through the electric auxiliary oil pump and dry sump pump. The dual clutch is cooled or lubricated by oil from the fully integrated transmission control electrohydraulic controller unit. Some of the oil is fed directly into the intake chamber or some of it flows together into the gear set chamber (dry sump).
The gear set gearing and shafts/bearings are cooled/lubricated by oil from the fully integrated transmission control electrohydraulic controller unit.
A lubricating spider lubricates the gear sets after load request.