[gtsiawd96]

Okay, Some may know, I'm an Audi tech been for almost 3 years now. I'm working on a 2005 A6 3.2l 41,000 miles at work, and have come across a problem I have never seen before. The car came in a couple months ago, leaking oil. Another tech diagnosed the rear timing chain covers where leaking oil. He removed the steel stamped covers, removed the old sealant and applied a new thicker bead of sealant and reinstalled the covers. Car returns 3 weeks later leaking oil again, I wasn't working on the car but I gave a quick look, and this time it didn't look like oil to me much lighter I said transmission fluid, there were drops of fluid coming off the bottom of the transmission bell housing and the oil pan where they met. And also fluid all over one of the transmission cooler lines witch sits directly under the bell housing/oil pan. Well, another tech installed an oil filter housing, thinking it was that, the filter housing sits behind the intake manifold on the top of the bell housing on top of the engine, the housing is made of composite and the oil filter is a cartridge and sometime can leak down the backside of the engine. Okay, well now this week the car returns, service manager gives me the car, wants it fixed right. lol.

Well like I had originally thought I was thinking the Torque converter seal, or the transmission cooler line was leaking since the fluid was very clean, oil is pitch black hasn't been changed in 6,000 miles. I removed the trans inspected the torque convertor seal it was dry alittle dampness but not the source of leak. So I narrowed it down to the transmission cooler line leaking. Reinstalled the 350lb transmission ugh. Replaced the transmission lines. Filled trans fluid, drove vehicle overnight, next morning Fluid Again. WTF!!

So I have come to find out today that the source of the clean fluid is actually 6,000 mile old motor oil. Where the transmission bolts to the engine, is actually the rear lower timing chain cover witch also houses the rear main seal, since the engine is chain driven it sits on the backside of the engine. The chain cover is cast aluminum and has machine surfaces that bolt to the aluminum block, it also bolts to the backside of the upper oil pan. There is a thin layer of sealant no gasket. This is the part I have never seen before, the tolerance is so tight and so small. That it is actually filtering the dirty black oil when leaking out of the lower timing chain cover, and its coming out clean. This boggled my mind today.

So tomorrow, I will be removing the transmission agiannnn to remove the rear timing chain cover, replace the sealant and various other small seals in the area.

Anybody else ever encounter this? I thought it kind of funny