I just wanted to post this story because a similar story helped me win my court case against my local Audi dealer. It's a story about confusing the Haldex with the diff.
I took my 2007 8P S3 (brand new to me) to my local Audi dealer for 60k haldex service.
When I got it back there was a whining noise from the rear of the car at 100km/h. I called the dealer and they sent a service manager out to me and he said it's a common fault with leaking diff seals (lie 1).
They got it towed to the dealer and I watched them drain the diff and it only had 50mls of oil in it. I told them I wasn't paying a cent. Their senior technician told me under his breath that someone had drained the diff.
They made a warranty claim by saying it had a damaged bearing (lie 2).
Warranty company wanted a diff expert to see the diff and they asked the dealer if they had serviced the vehicle. Dealer denied servicing it and said it just came in with a noisy diff (lie 3).
Diff expert said bearings are fine and it looks like it was accidentally drained and driven empty.
Warranty company accidentally approved the claim but only paid the first NZ$5800, leaving me with over NZ$1800 to pay.
They had in fact drained the diff instead of the Haldex and then double filled the Haldex. This explained the empty diff and also why the underside of my car was coated in Haldex oil (yellowish and odourlessish, I know it's not a word but I like it anyway) and why my sway bar was recently wiped clean. This was further substantiated by the blatant dishonesty that the Audi dealer was showing.
They had tried to steal from me from the word go and if I didn't have a warranty I would have had to give them the car to pay the bill. Most of their customers would probably have paid the thousands of dollars and not even questioned them. Luckily I have more sense than dollars (I'm not saying I have a lot of sense, I just have very few dollars) and I did question them.
I took them to court to get my money back and won thanks to the diff specialist but also because I was able to show the judge stories like this one.
Moral of the story is... Diff and Haldex drain plugs are easily confused.
Or maybe the moral is... Never trust someone who profits by saying trust us we are highly respected and very honest.
Or maybe... Never trust someone just because their shop has a big fancy sign out front.
Or maybe... Experts and amateurs are often only seperated by arrogance.
I hope this information can help someone else.
p.s. Sorry, as if this post wasn't long enough.... Can anyone tell me if their Haldex to main driveshaft flange has 4 nutless bolts sticking out about 25mm? When I got my car back I put it on my hoist and I thought it looked like something was missing. Maybe a dust cover or counter weights or something over the flex disk.