Fluid - ASMT: Description and Operation

Oil Types/Oil Fill Quantities/Oil Chambers/Change Intervals

Due to high shearing strains that occur in the differential, two different oil chambers are used in the Porsche Doppelkupplung transmission.







The oil chamber for hydraulic oil is shown in red, while the oil chamber for gear wheel oil is shown in blue in the illustration above.

2.95 liters of Mobilube PTX Formula A (SAE 75W-90) GL4.5 are used in the transmission for lubricating the gear wheel set. 5.2 liters of Pentosin Gear Oil FFL3 are used as hydraulic oil.

The change interval is 56,000 miles (90,000 km) for hydraulic oil and 112,000 miles (180,000 km) for gear wheel oil.

Oil filling







The correct hydraulic oil level is important for operating the transmission without running into problems. The following preconditions must be met in order to check or correct the oil level:
- Engine must be idling
- Vehicle must be horizontal in both longitudinal and transverse axis
- Hydraulic oil temperature between 86° F. and 104° F. (30° C and 40° C)
- Selector-lever position "P"
- Clutch cooling volume flow must be switched off (using PIWIS Tester in Oil fill mode)
- Retain the described states for approx. 1 minute to allow the oil to settle
- Open screw plug on oil overflow bore and collect emerging oil until only drops of oil are emerging
- Once there is no more oil emerging, top up the clutch fluid until oil emerges at the oil overflow bore
- To avoid damaging the clutches, the procedure must be completed within 5 minutes (PIWIS Tester exits Oil fill mode automatically after 5 minutes)

The correct oil level is also important to avoid damaging the gear wheels in the transmission. There is also an overflow bore for this, which is located on the opposite side. The oil level can be checked in the usual way here.