First of all, I wish to thank the forum members for their detailed information on how to change out the ZF transmission fluid. With the aid of these various threads I was successfully able to change the fluid, pan, sleeve, and filler plug. Thanks again.

The fluid that came out was pitch black color but still seemed to flow nicely. It didn't smell burned or anything.

Just for the fun of it, I sent in a sample to Blackstone Labs. I attached the results to this post.

 

Says it all in my opinion.

Just proves how silly that sealed for life sales statement really was/is.

ZF down here are recommending a fluid change at approx 80k kms on Ford and others with that unit fitted.

 

Thanks for posting this....

Rick (joycesjag) and I changed the fluid in my wife's 2006 XK8 about a month ago as part of me trying to address her intermittent rough shifting complaints. At about 67,400 miles, the factory fill of Lifeguard 6 had turned light brown from its original golden color. We did not find any metal shavings on the pan magnets. All things considered, I'm very glad we changed the fluid. Better to be safe than sorry as they say....

My 2005 S-Type is pushing 77,800 miles now. My plan is to change its factory fill of Lifeguard 6 at 80,000 miles or so....

 

Thanks for posting your ATF analysis results.

 

This is on my too do list...

 

Yup.... Lesson to all, CHANGE THE FLUID!

That said, the viscosity numbers are very promising. Considering the level of metals present in the sample, you got that stuff out just in time. I would also say that ZF really needs to come to grips with service intervals. Mercedes did..

The 7 speed in the wife's R350 was advertised as a sealed for life transmission when it was sold in 2006. By 2007 they had some goofy 39,000 mile service then leave it for life. Then they revised that (in 2008 I think) to every 40,000. My Chrysler has the Mercedes 5 speed transmission and it too is a sealed unit (but serviceable like the ZF) and also comes with a service interval of 60k.

I have always been an advocate of following manufacturer's specs when it comes to service but it is here where I really disagree. I keep being proven right. In some cases it is a manufacturer's change of position or in this case, the clear evidence in the OP's fluid analysis.

I think the ZF should state: 75k service interval under light use, 50k severe duty. BTW, I drive my car pretty hard, so I always follow the "severe duty" intervals.

 

Yeah, I was also a bit surprised with the viscosity numbers as well. However, now that I think of it, I recall seeing a post somewhere in a BMW forum showing very good numbers at 95k miles.

My Volvo's unit (not ZF) is also "sealed for life", and my local Volvo dealer refused to change the fluid. However, last month during my usual service visit, the same service adviser who once refused to change the fluid, now recommended that I do change it out. So maybe the car companies are changing their minds...