X5 4.4 - Sludge in engine and oil filter housing... help!

[Mikedd]

Originally Posted by JCL

Have you ever worked overhauling transmissions? I suspect not. It isn't a non issue to those of us who have, but it may be to you. That's cool.



No argument. Only issue is, is it relevant? Are X5 transmissions failing due to lubricant quality? Not according to the posting history on this board and others. Sensor failures, actuator failures, programming failures, are all unrelated to fluid quality. They are at the root of many early transmission failures. Changing the fluid won't improve your odds.



Then you should change your transmission fluid. You are the only one who will live with the consequences, so just do it.



My reasoning is based on working in a shop. I can't tell you what to do, just that I won't change my own transmission fluid. I do believe in preventative maintenance. I just believe that in the case of the X5 transmission, the risks outweigh the benefits.



I wasn't referring to those cases. I was referring to the multiple cases where a transmission worked fine, up until soon after it had the transmission fluid changed. It happens too often. Technicians in transmission repair shops know about it. You can discount it if you like. It is the reason that those of us who have rebuilt transmissions make judgement calls on whether to change the fluid in this case. I think there is a small chance of a fluid change causing a failure, overall. I think there is even less likelihood of degraded fluid causing a transmission to fail. Look on this board for all the posts that start off "FML, my transmission failed, and wouldn't you know it, I even changed the fluid recently". If you choose to take the chance, no problem, rest easy in the knowledge that your transmission probably won't fail due to a fluid change anyway. Just don't expect it to last longer, that is my point.

We did a poll on here on that very subject of failing transmissions after fluid change. Mind you it was far from statistically accurate but I was very surprised to see that no one had reported a failure after fluid change and 10K mles after. I was really surprised and the more I asked the more of "urban legend" it seemed to become. Certainly out of proportion to reality.