2013 Cayenne Diesel Fluid Leak

[stronbl]

2013 Cayenne diesel, 15,970 miles.

Just completed oil change #3 (May 24th) and I noticed fluid has leak onto the transmission bell housing (no leaks previous two oil changes). At first I thought I might have a transmission or transfer leak, but the fluid is motor oil or gear oil as it is quite dark (almost black) and since the bottom of the bell housing is the low point it makes sense it would collect in that spot. There was a fair amount of fluid on the underbody engine guard, about 1/2 of a blue Scott's shop towel after clean-up. I also cleaned around the housing and electrical plug area and put everything back together.

Since the CD is my daily driver I drove for the next week and checked underneath again (May 31st). More fluid, same color and character as the week before. The attached picture is from the may 31st inspection. You can see it is a slow leak, but a leak nonetheless.

I took it to my Porsche service center and they confirmed fluid but since they had no maintenance record (I do my own simple service -- oil, brakes etc) they were not ready to make a warranty claim just yet. They too cleaned it up and we agreed I'd drive for another 2 weeks and check it again (with more pictures to document the issue). If fluid leak continues then I'll bring it back in and we'll try again for a remedy via warranty. I'll check it again this weekend and see how bad it is, and if I can trace the fluid upward to a possible source.

While I wait, I have a couple questions for the forum:

1) anyone else experience a fluid leak similar to this - probably motor oil - and if so, where or what was the source/cause?

2) ideas as to what may be the cause - engine gaskets/seals gone bad, etc.

Thanks. I appreciate any insights and/or suggestions.

[gnat]

My 3rd OCI is coming up in a few hundred miles which I'll be doing myself so I'll keep an eye out.

Did the filter cover get torqued back down properly? Had your oil level changed at all since the last OCI?

While mine was in the body shop I opened the hood and found some black liquid on the underside of the hood with a few drops on the engine cover. Looked like oil, but I have no explanation of how it got there and it hasn't come back in the last ~5k.

[stronbl]

I checked the torque on the filter cover and it was good, couldn't see any oil leaks from that area. Oil level from previous oil change was at most 1/4 L down which I added, very minor. I'm beginning to wonder about some sort of gasket seal leak on the motor. I also just got back my oil analysis from Blackstone and they said it looked good but the viscosity was on the low side, but not an issue. Given the rest of their analysis they concluded everything seemed ok.

The mystery contunes ...

[dougg996]

It looks like the same problem I experienced earlier this year in my 2010 958 Diesel. My car was still under extended warranty and my local Porsche Centre told me they had seen this problem in several other 958s in the last couple of years. The leak I think was transmission fluid because I was told that when it was repaired, that the sump oil was not affected. The repair took about a week and was an 'engine out' job requiring new seals between block and transmission from Germany.

[stronbl]

It looks like the same problem I experienced earlier this year in my 2010 958 Diesel. My car was still under extended warranty and my local Porsche Centre told me they had seen this problem in several other 958s in the last couple of years. The leak I think was transmission fluid because I was told that when it was repaired, that the sump oil was not affected. The repair took about a week and was an 'engine out' job requiring new seals between block and transmission from Germany.

Thanks for the info. I originally thought transmisson too but after discussion with the dealer wasn't so sure. I'll keep monitoring and then head back to the dealer probably next week if the leak is still there. Maybe I'll have something new to report.

[stronbl]

A short update for anyone following this thread. After a week of driving the CD, I pulled the engine protection covers off and examined the leak area again. There is still a leak but it is small. I've attached another picture. There was no fluid on the under body panel after the week. My driving during the week was a few trips around town and daily commute to/from work. City streets and short highway trips. No towing loads or heavy cargo.

Upon examination of the leak area, I attempted to trace back to the leaking source. As far as I could tell, it appears the leak source is the interface at the bell housing. On the attached picture I highlighted this area with a yellow box. I could see fluid in the gap shown by the yellow box up to the left most bolt. The droplet in the picture is formed at that location due to it being the lowest point of the bell housing. So my original thought being a transmission leak seems to be correct. If I had to guess at this point I'd say it is either an internal seal gone bad or a failed gasket around the housing. Either way it would seem the transmission will need to be dropped to find the true culprit and remedy the leak. I'll be taking it to the dealer soon.

Thanks for the comments and suggestions so far. If anyone else has experienced a leak like this, I'd most definitely like to hear about it. Hopefully you haven't and mine is simply an anomaly to the CD. It's been a great vehicle so far.

[gnat]

My 3rd OCI is coming up in a few hundred miles which I'll be doing myself so I'll keep an eye out.

Finally got around to my OCI tonight. Mine too has signs of something leaking right where the transmission meets the engine. No drips like your pic and nothing on the tray, but obviously not as it should be.

I'll call my dealer tomorrow and get it in to them to take a look at.

[stronbl]

Gnat, sorry to hear you have a similar or same issue as I am having, albeit less volume of fluid. 

 

My dealer/service manager and I agreed to a process to try and isolate this issue.  We all agree there is a leak or a seep (I tend to think it is a leak but I suppose that is a definition) and they definitely want to fix it, it's just we are not sure of the cause/source.  In any event he added some tracer and I'm to drive at least 400 miles and then we'll re-check the leak/seep area.  Since this is about the lowest point, fluid will collect there even if it is not the actual leak spot.  With the tracer we are hopeful we will isolate the source and start a remedy.  I'm at 700 miles since the tracer so I need to call and bring it in so we can take a look and see if there is more to learn.  I'll try to get in this week and report back. 

 

On a positive note, I've not had to add any oil since the last change (2600 miles ago) and the transmission and differentials all seem to be working fine.  Nothing out of the normal.  I wonder if this could be a seeping issue associated with the diesel motor and not a precursor of a bigger problem, he says optimistically ....

[gnat]

I dropped my off today (and got to see a CGT up close and personal too!). I'll update with anything I get back from my SA/Tech.

I checked mine over as well as I could and there was no sign of it coming from above that I could find including reaching up around it and wiping with a shop towel. My best guess is the seal between the transmission and engine. Out of curiosity, what is your build month? Mine is a 10/2012 build.

As far as the oil level, mine hasn't burned any oil over the 3 OCIs.

[stronbl]

I dropped my off today (and got to see a CGT up close and personal too!). I'll update with anything I get back from my SA/Tech.

I checked mine over as well as I could and there was no sign of it coming from above that I could find including reaching up around it and wiping with a shop towel. My best guess is the seal between the transmission and engine. Out of curiosity, what is your build month? Mine is a 10/2012 build.

As far as the oil level, mine hasn't burned any oil over the 3 OCIs.

 

My build was completed on 10/1/2012 !!!  Too funny.  Dealer will pull the engine mid August when I have time to leave it with them.  They'll check the dye markings and start replacing seals, gaskets, and whatever else they deem necessary to remedy the leak.  Estimated a full week's worth of work.  Covered by warranty. 

[gnat]

That is too funny. I believe my build was 10/7 if I remember correctly.

 

I got mine back today. They are calling it "seepage" (which is probably a fair term), but the best part was the official response being "some leaking is normal". I kid you not.

 

I couldn't help but laugh hysterically at that. When I explained my thoughts on that being "normal" and how I find it par for the course with the typical "burning oil is normal" he agreed off the record that he suspects there is more to this.

 

I'll keep watching it and bring it back in next time there is significant build up (or if it progresses). Mainly as long as it's documented as early and often as possible I'm good for now.

 

Will be interested to see what happens with yours. Two samples don't make a statistic, but I find it interesting that both ours were built right about the same time.

[stronbl]

This is the exact same scenario I went through, language too.  My shop needed to have air tight documentation that it was actually a leak and not a seep.  I had them clean everything up and I drove another 100+ miles and brought it back in.  Fluid appears again but not enough to drip onto the under body panels.  So we added dye and I drove for 800+ miles.  This time we had leaks onto to body panels and they agreed it was an issue.  Given that the remedy is dropping the engine, I can see why they want to have air tight proof there is a leak and not a seep, should PCNA question the expense. 

 

I bet if you have them clean it up, and drive a while, eventually you too will have a leak.  May take a few 1000 miles but eventually it will qualify as a leak - the good news is, if it is like mine, the CD is still fully drivable and the amount of fluid that evetually leaks is minimal, a few ounces in total.  Just watch your oil level just in case.   When I get the work done in mid August I'll report back what was fixed and/or replaced.  I suspect there are some bad seals or gaskets and maybe some bolts have backed out but I'll know for sure in about a month. 

[gnat]

Engine oil is what my SA/Tech think as well, but given the location my gut says transmission fluid (which of course can't have it's level checked easily). I agree that I think it's just a bad seal.

I also understand their reluctance to drop the engine, but unfortunately Porsche has a history of ignoring and discounting engine related issues so I am a bit jaded.

[stronbl]

Update and remedy:
 
Ok, my CD is fixed and hopefully leak free.  As noted above this was indeed an engine and transmission out job, including air suspension in the front.  We replaced the bell housing cover.  The explanation to PAG was the cover was slightly warped and was not providing a proper seal.  Although the locktite sealant was present after removal of the cover, there was one particular area where it appeared to be a "breach" in the sealant and was the area of the leak.  This is a complicated and time consuming job, but very doable for properly trained service department.  Of course the bell housing cover was not available in the US so one had to come from Germany.  Attached photos shows the area of leak (yellow circle) and engine timing chains with bell housing cover removed. 
 
Once the CD was put back together, I cannot tell any difference in the vehicle - engine, transmission, etc.  Also I want to says thanks to Gunter and his team at Fremont Porsche for a great job and working with me through this involved process.

 

[gnat]

Thanks for the update. It's been about 2.5k since my dealer last looked at and cleaned mine. I need to crawl under and see how it is doing.

[gnat]

Just did my 20k/2yr service the other day and found no sign of fresh leaking on mine. Still looks like it did I wiped it off about 3000 miles ago, so hopefully mine was just a spill from above after all.

 

Thanks again for all the info about your issue.

[Dunerking]

Just going through this same scenario with our 13 diesel. We bought it used with 19k miles in August. My wife had mentioned to me that a low oil warning came up after owning it for 4-5 months(1500 miles). Thought it was strange that it would be low,so I topped off. Then when I preformed my first oil service I had noticed a drip coming off of the "skid plate/cover" and traced it up to the trans motor connection. Took it to the dealer where did (just it was mentioned here) a tracer fluid and had her bring it back after 500-ish miles. 

She just dropped it off today,so I'll report back after the get into it. Thanks again for the helpful forum! 

[dollarlongnecks]

Just had a similar leak on my 2013 diesel fixed under the class action extended warranty. When I dropped it off, I mentioned this thread to the shop foreman, and how i'd read about an instance of a warped bell housing cover. He said that sounded rare, and that it was likely leaking from the bolts where they hadn't been sealed well (had a real seal replaced previously). Well, they found some additional "seeping" in other areas, and they ended up replacing the bell housing cover. I didn't get a chance to talk to the foreman afterward, but the paperwork says "warped chain housing cover" and 17 hours for R&R, so this was a big job. I won't be back under the car again for a while, since I just changed the oil, but I expect it to be nice and dry the next time I crawl under there.

Edited August 20, 2017 by dollarlongnecks
misspelling

[Dunerking]

We  got ours back from dealership(2.5 weeks)with about 3-4 pages of seals and everything else they replaced. So far no more leaks,and hopefully that will be the end of that. Wife was done driving the gasoline loaner Cayenne. 

Bummer was with the whole time they had it,I wish they would've done the verification deal for the diesel fix. She ended up having to drive back there for the 15 min verification. 

Edited August 21, 2017 by Dunerking

[Dunerking]

The paperwork said replaced oil guide hosing. Going to keep an eye on it and make sure the bell housing cover isn't warped like some of u guys dealt with.