RichieRoo

The transmission fluid type
Originally the tiptronic was filled with Dexron II. This has now been
superseded - Dexron III is now the equivalent which is recommended.
There are a number of brands available which meet this standard.

In total the transmission holds 9.5 litres of fluid, however even if the sump is
removed you will probably only need 5 litres of fresh fluid to refill the system
as a large amount is retained by the torque converter and cooling system.

Fabricating 'fast fill' hose connection
To use Porsche's 'fast fill' connection (which is located adjacent to the ATF
level gauge) the fluid has to be slightly pressurised because the connection
faces downwards. I found a neat way to connect a bottle of ATF to a
garden hose, which slips over the connection perfectly.

All you need is a garden hose connector which comes with a thread adapter
(see photo), a couple of rubber O-rings and some garden hose (internal
diameter of approximately 12mm, which is standard garden hose in the UK).
Make sure the hose is new and clean to avoid contamination.

Then carefully drill a 25mm hole exactly in the centre of the plastic cap of
the ATF bottle. Assemble the pieces and you're ready to go.

Filling the transmission
Unscrew the 'fast fill' connection, attach hose on to fill tube (the hose should
be a good push-fit) and squeeze the ATF container. The entry hole is small
so it may take awhile, but eventually you'll see the fluid level appear on the
sump gauge (it helps to have an assistant squeeze the bottle so you can
keep an eye on the gauge). Keep filling until the level is 10mm above the
highest 'MAX' mark.

Now start the engine and, ensuring the footbrake is depressed, select 'D'.
Wait a few seconds and then return the lever to 'P'. If you glance at the ATF
level gauge back under the car you'll see that the level has dropped
dramatically. Turn the engine off and add more ATF. Repeat this cycle of
adding more ATF until the level is about 15mm (dependent on fluid
temperature) above the lower 'MIN' mark even when the engine is running.

I originally, incorrectly, assumed that if the gauge level showed at the top
'MAX' whilst the engine was off and the car had been standing there must
be enough ATF in the sump and it would be overfilled if I added more.
This is not the case.


Symptoms of low ATF
When stationary, at idle, the engines revs will occasionally dip and the
transmission tries to pull (more so than the usual amount of 'creep').
This may even cause the car to stall once in awhile.

The car will frequently, but intermittently, stall as reverse gear is selected.

Gear selection, especially up-shifts, will not be perfectly smooth. This will be
most noticeable when a higher gear is manually selected whilst revs are low.

Thank you to nirich (Nick) and all the Rennlist members who help me on this.