VR_Life

Leak located - coming from a vent hole on the drivers side.
<img src="http://pictureposter.audiworld.com/58573/img_2819.jpg">

Any L10 guys that see tranny developing a strange leak should watch this spot - the trick is that it's impossible to get a hand or mirror up into this spot when the tranny is mounted and the engine is running - which is the only time this vent hole leaks :-/

This special vent hole is designed to vent ATF in case a special double seal on the final drive gear of the Front Axle (confusing name it's actually the shaft/gear going rear of the tranny section and into the center diff).

After speaking at length to the local ZF guys and L10 I have come to the conclusion this is L10's fault.

When L10 rebuilds the tranny they must remove the diff section and then the final gear. However when re-assembled this final gear has a double seal and must be inserted onto the shaft using a special ZF tool, otherwise there is a severe risk one or both seals will be damaged. Bust the Tranny-side seal and ATF will escape out the vent hole. Bust the Diff-side seal and Gear Oil will escape.

Sam @ L10 confirmed they do not use the special ZF tool.

Sam recommended I could replace the shaft seal myself, removing only the center diff but after talking to ZF I don't believe the main shaft seal is the cause, and I'm having the final gear's double-seal repaired by ZF and the gear remounted ... properly.

So, I had to take out the entire tranny myself on jacks - no other choice.

Out damn you, out !
<img src="http://pictureposter.audiworld.com/58573/img_2843.jpg">

Dropping a load ...
<img src="http://pictureposter.audiworld.com/58573/img_2845.jpg">

Mission complete - whew !
<img src="http://pictureposter.audiworld.com/58573/img_2850.jpg">

The offending hole ...
<img src="http://pictureposter.audiworld.com/58573/img_2851.jpg">

God help me getting this back on - last time I put it in was on lift and it was not fun. I don't think my chances are great on jacks :-/

Now shopping for a better tranny jack.

daves4

Is L10 compensating you in any way?

dscottjr

Another crappy level 10 story:-( Man that sucks...

s4net

Great detective work. Is Level 10 the only shop that does the trans hardening needed for K04's?

StreetCrawler(Cole)

There are some other shops working on them also that don't offer full rebuilds to the public yet. 3Zero3 Motorsports in Denver, CO is working on this project as well. They have solved some L10 issues for me.

Mike@IngolstadtWest

Is this a yes or no issue? My customer has an L10 gearbox which has about 7,000 miles on the build. If it isn't doing this now, is it safe to assume it won't?

Thanks!

MCH 2.7t

That really sucks! Sorry for your troubles. Good luck with the re-install

FBAnder

Good luck getting it back in and I hope L10 compensates you in some way, shape, or form though I highly doubt it.

FBAnder

IIRC, David had this problem since he installed the trans himself and has been attempting to track it down.

Skydive@AI

My L10 transmission only had to go back to New Jersey once, and Sam paid for most of it. It has worked fine since, in two different cars. (By the way, I am the customer that Mike@IngolstadtWest was refering to.) Anyway, we've got the motor and transmission out on the table right now, and it would be great to diagnose this problem now if it exists in my setup.

In fact, I took the opportunity to send my torque converter out for internal inspection and reinvention given that the transmission is out anyway, and StreetCrawler had expressed issues with his. I should have a full report back this week. (Externally, considerable galling was visible on the converter shaft itself.)

Fortunately, there are a couple of local ZF guys around, so if my gearbox has the issue that David described, we can get it resolved without all that much effort, in relative terms.

I'll report back when I hear from my torque converter specialist.