Kinetic0510

<center><img src="http://www.chrismondragon.com/Audi/leak1.JPG"></center><p><img src="http://www.chrismondragon.com/Audi/leak2.JPG" border="0">
<img src="http://www.chrismondragon.com/Audi/leak3.jpg" border="0">
<img src="http://www.chrismondragon.com/Audi/leak4.jpg" border="0">

Certainly looks like oil to me, the first pic should point out locationally where the leak is comming from at the front of the car directly where the belly plate ends. Looks like the leak is either comming from the diff or something above it. I should also note I've been having a strange clutch problem since I've owned the car (2 months). The clutch acts perfectly normal for the first 30 mins of driving then after that it seems as though the throwout bearing and/or pressure plate stops doing it's job and all disengages are rough and abrupt. I should also mention I get no slippage once disengaged and in gear, only seems to be DURING a disengage. I'm wondering if 'whatever' is leaking here is leaking onto the clutch componets and causing it to lose it's friction. Please let me know what you think. Thx in advance.

CTMechE

Or possibly the previous owner did it, since you've only had it 2 months. The belly pan looks damaged to me.

RKA

Rear main seal is behind the engine where it connects to the trans.

Your theory of oil contamination on the clutch is plausible. First figure out where the oil is leaking, then determine if there are openings in the bell housing at or below the source of the leak, where oil seems to be working it's way in.

JAFO

had some odd effects on the clutch which only started after it was driven for awhile. this looks a little red for motor oil. imo pulling the trans is your next step. this isn't going to be cheap!

Kinetic0510

but that damage looks completely unrelated to whatever is leaking. As you can see, there doesn't look to be any physical damage on the diff itself (impact scrapes, etc). I have a feeling that leak is comming from above and ending up leaking off the bottom of the diff. If that assumption is correct and I have oil leaking into the bell housing onto the friction componets of the clutch, then that would explain my clutch issue that no one else on this forum has ran into.

RKA

Search the S4 forum...months and months of clutch issues eventually boiled down to a coolant leak contaminating the clutch assembly. See if you can do a search to see what the symptoms were.

Raullopy

had to do mine at 90k they go bad. suckd because it a big job from a mechanic or stealership. About 800- to a grand.

Kinetic0510

so if it is that, where exactly is the leak comming from? And is that motor oil?

Kinetic0510

when I capture the fluid that's dripping down on a plain white towlette the color is that of a very pale green and looks to be diluted somewhat with water (or a clear substance). I used the same type of towlette to wipe off some oil from my dipstick to compare the two. Oddly enough, there are differences between the two. My motor oil is much darker and thicker compared to the mystery (greenish/yellowish) fluid that seems diluted with something clear. However when you run your fingers across the mystery fluid it seems oily (almost identical to mineral oil, not motor oil). The smell is also different between the two fluids.

What other fluids are in our cars that compare to this mystery green fluid? I'd typically say leftovers from having the A/C on, but I haven't used the A/C in days.

RKA

(hopefully you'll say pink)

Can you compare the fluid to the stuff in your power steering reservoir?

If your car is a manual...can you put the car up on stands, and get a light up above the bell housing? Look for signs of leakage around the slave cylinder for the clutch. If there is leakage there, it's brake fluid (yellowish/clear). Take a sample from the brake fluid reservoir under your hood, and compare to the mystery stuff. A friend of mine (digit@lex) found this leaking a few weeks back. He unclipped the line running into it, pushed it back in, and bled the clutch. He hasn't seen anymore leaking since. I guess the seal just worked it's way loose a little bit, causing a slight leak.