elpanson

I am new to Audi's and realize they can be great but problematic. Here's my problem:

-I started leaking what I thought was oil because it was brownish but clear, got the car on jacks , cleaned the oily areas and started the engine. The liquid is like ATF fluid and the area is between the pan and the housing (maybe I can insert a photo)

-Googling has come up with the main seal leak as the culprit but also to other reasons for a leak in that area


Here's the leak area

AAA picked me up today, I stopped because there was slight smoke from engine. 2 days earlier there was erratic sputtering from car but drove fine otherwise, shifted into gear (automatic) without problem. Today I decided to take 600 lbs of cement to dump (about 6 miles) and thats when I noticed a weird screeching/laser sound from engine. Left dump about a mile, saw leaking fluid, stopped and waited for AAA. Could of the 600 lbs of weight blown the seal?

I thought it was oil because it was brownish but clear like coolant fluid but still gritty like ATF fluid with a slight greenish tint. Once home I cleaned the undercarriage, started the engine and about 30 seconds later the leak started from the area I posted. This is where I am at now. Hoping you experts can clue me in. Thanks.

-Car specs: 2001 A6 Avant wagon, Automatic with 114k miles.

elpanson

ps, the leak is constant and not a slow drip.

SloopJohnB@mac.com

a constant drip should show up as oil level drop.

This could be a cam cover gasket or chain tensioner gasket leak as well. There are other potential culprits under the V8 or V6 intake manifold as well. But the probability is high that it is a main seal leak since it just started rather than coming up after a recent maintenance event. Did you just do something maintenance-wise to the engine, BTW? Like change to a 0-20W or synthetic engine oil? If so, get thee back to a decent 15W-40 or 10W-30 oil. Synthetics have a bad tendency to eat out or dissolve false seals made by varnish buildups although no where near as bad as 30-40 years ago.

Otherwise, R main seal leaks are largely a matter of ruling out everything else. If you put a UV dye tracer in the engine oil and let it run for a few minutes, especially since it's a constant drip, you should be able to rule out oil leaks from the back of the engine higher up, like the rear of the heads.

After that, what's left is the rear main seal. Engine or trans has to come out to replace the rear main seal. Before I did that I would probably try an engine additive specifically made for main seal leaks.

elpanson

Thanks for the detailed response. I will try anything before a tranny pull and was hoping someone might of had the exact situation with an easier solution.

I couldn't find a good instruction on removing the A6 C5 wagon tranny though.

the_duke

Audi doesn't make a wagon. You have an Avant. Transmission removal depends on what engine and transmission you have in your car.

elpanson

Thanks, I was being synonymous by calling it a wagon, I guess living 15 years in Germany has rubbed off on me. One thing I learned about the Audi through google is that they are the same engines as in the VW Passats and such which have better repair videos available. One thing I liked about the BMW's is that there are a ton of videos and help links out there.

Audi is rather very specific but I am on a Russian site that has a bunch on engine info though.

I appreciate your help.

Prospeeder

Its the valve covers, cam plugs, and timing chain tensioner gaskets leaking. All of them do it eventually.

elpanson

I checked the valve covers, cam plugs and timing chain tensioner external areas but cannot see any leaking.

elpanson

Hey Folks, update:

-got me a vag-com cable
-got a new trans filter/gasket
-refilled trans via monitoring temp and going through gears
-when I got to almost ending the procedure she got to about 35 degrees and the transmission leak started at the same spot I posted in my first pic.

Damn.

I think it might be my rear main seal?

Things I noted:

-Tranny fluid was red, leaking fluid was same red fluid.
-Flywheel sprockets are dry
-when I was shifting gears during refill, it made a ratcheting sound when I shifted back into park (P-R-N-D>D-N-R-P).
-No other leaks can be found looking above or below engine/tranny.

Maybe my latest findings can give someone more experienced confirmation that I have a rear main seal leak.

Thanks.

Prospeeder

You can try to replace the torque converter seal, but what I find is the front pump on the transmissioin fails and then it leaks fluid from the bellhousing like that. Unfortunately, you probably need a transmission.