Haldex Oil and Filter Change
This Technical FAQ (How to...) has been carefully compiled by John Handford
You can change the oil with the car up on a pair of wheel ramps because you don't need to have the caulking gun vertical. You can bend the nozzle in the middle, so the caulking gun can be horizontal.
Just get the oil warm after a drive, clean up the drain plug and surrounding area (important) and then drain it out by removing the plug with an Allen key.
If you change the filter this is the most awkward part of the process. If you have the official Audi tool you'll find it fouls on the under cover. You can take the under cover off but it's a pain, or you can cut a slot into the cover to make room for the tool handle . I'm not sure about access with the alternative stamped out flat tool with the square drive hole.
When you come to put the oil in, before you attach the nozzle to the cartridge, screw the nozzle, on its own, into the drain hole - it will bite into the thread. Kink ther nozzle in the middle to form a 90 degree bend but squeeze it at the edges of the kink with a pair of pliars so it doesn't block the flow. Then screw on the cartridge/caulking gun and pump the entire contents inside.
Next is the tricky bit. Have the drain plug handy and with the Allen key already inserted into it (this makes it easy to handle), put your clean finger on the casting underside, up against the cartridge nozzle tip. In one deft movement yank out the nozzle from the casting and immediately slip your finger over the hole to stop the oil coming back out. Now hold the drain plug, on the Allen key, next to your finger and with another deft movement, slide your finger away whilst immediately blocking the hole with the filler plug and screw it in.
That's all there is to it
See these two posts for more details:
http://www.tt-forum.co.uk/ttforumbbs/viewtopic.php?t=79020
http://www.tt-forum.co.uk/ttforumbbs/viewtopic.php?t=62767
