I used Royal Purple. I'm not sure if it is compatible with you transmission.

Amazing...both you for driving ~34k/year and the X for never leaving you stranded!

This whole transmission thing has me wondering, too, since I have 183k on the original trans in my 2002 4.6. Every now and then I think it's starting to "feel funny", but then again it's my only true automatic so I don't know what else it's supposed to feel like. I'm thinking about the fluid change, but know that complete replacement of fluid on an older unit WILL cause problems because it is too clean and there is nothing left behind to "fill the gaps" between the (now worn) gears. Sounds like you have cracked the code to just refresh the fluid, but not a complete changeout.

Without dropping the pan and having to replace gaskets and filters, too, how do you change the fluid such that there is still just enough "gunk" left behind?

I don't really agree with your transmission fluid analysis.

It is not a given that a fluid replacement will cause a problem. It may do so. There are lots of examples of a fluid change causing a problem, but lots is a relative term. There are more examples of a fluid change not causing a problem. The real issue is whether there is any benefit to changing it other than the feel-good factor.

Any transmission fluid change (other than a power flush) is only going to change 50% or so of the fluid, because you can't drain the torque converter. The old fluid doesn't fill the gaps due to its thicker consistency, it is more that the new fluid contains fresh quantities of detergents that can loosen the deposits built up over time inside the transmission, allowing them to shift from where they were doing no harm, to somewhere that they do cause harm, like a valve body, with many small passages, or an actuator or solenoid.

Common wisdom is, if you are going to change it, to change it early and regularly so that there is no buildup inside the transmission. Also, common wisdom is to change the filter every time you change the fluid. Finally, common wisdom says to use approved fluids that meet the original spec. I agree with all of the above. However, wallyx5 didn't do any of the above, but had great results nonetheless. My point is that I don't think fluid has much to do with transmission failures, whether it is changed or not (unless you use a bad fluid that in and of itself causes a problem)

People are paranoid about X5 transmissions, and worry endlessly about them, but look at a few facts:

• Different models of X5 have either GM or ZF transmissions, and either 5 or 6 speeds (different models). Yet all have similar transmission issues. Why would all versions have problems if there was a weakness in the transmission design? Wouldn't one be better or worse? I suggest that it isn't due to the design.
• Some run for a very long time. That demonstrates that they are capable of running for a long time, without wearing out. I think this one is the longest on here, but there are others at high mileages as well.
• Transmissions have reported to have failed for a wide variety of reasons. It is because something broke in them more often than not. Breaking is not the same as wearing out. They are entirely different failure modes. Breaking can be a weakness in the metal; a failed solenoid, sensor, or controller; a failed actuator; failed wiring harness; or a software problem. Transmission used to fail years ago because the clutch plates were worn out, for example. Too much friction and heat. These aren't failing like that, they are simply breaking randomly, in many different ways, at a wide variety of mileages from 10,000 on up. There isn't a common failure time or mileage from the reports on here, they are spread all over.
• Given the above, it doesn't appear that there is much to be done to change the results of the transmission lottery. You can't change something which is random. It may fail. It may not. Abusing the transmission will speed it up, but not much else seems to matter.

If you want to change the transmission fluid, you should. If you don't want to, that is fine as well. There are arguments both ways. However, wallyx5's great results with his X5 have resulted in three posts about his transmission fluid practices. I think they are entirely irrelevant. He has shown that driven properly, the vehicle can run a long time, and that is great news. I just don't think it results in transmission fluid change recommendations.

I hadn't congratulated you yet, and wanted to. It is terrific to see that these vehicles can perform in the way they were designed for. I think your driving style (somewhat aggressive as you describe it) doesn't hurt, and that there is some truth to the thinking of driving these vehicles as they are meant to be driven. I also suspect you don't go so far as to abuse it, and there is a difference between aggressive and abusive.

I also think that your high mileage suggest you don't do a lot of short trips, that you get it hot regularly if not every day. That is critical IMO.

Congratulations again.

Congratulations! May you reach another 100,000 mi

congrats - that is some serious mileage. I'm just barely 1/3 of the way there myself. There are reports of several E38's with 200K+ and I recall seeing a few up over 300K, many on the original transmission as well. So it can happen, although it doesn't always work out that way either - my buddy lost his trans at 130K miles or so, but rebuilt it and is now going on 190K in his E38. Since E38 is basically the same generation and drivetrain as the V8 E53.

:iagree: It's really a lottery and you just have to wait and see. If you do decide to change the fluid and filter I would recommend the OEM fluid, and do it earlier on. Like I did on my Mercedes, with 40,000 miles. I just went with the partial fluid change and Royal Purple fluid because it gave me some piece of mind. But at that point of 188,00 it did not experience any problems that prompted me to do it. I just felt like doing something.

wow thats great

i think its the high miles per day that does it, i think its another case of use it or loose it.

i do about 100 / 150 km per day and have not had car troubles in years

i have done 20,000 km in 7 months in my new to me X5 3.0d and i love it

after browsing here for a few months however ive started to worry.

so its good to see high mileage stories

I just got to thinking, I'm sure the Honda/Toyota people out there would chuckle at all this, as this is not such a rare thing for them. I guess I am one of them, since I have a Land Cruiser in my stable.

I love my BMW's though!


Any super high mileage V8's out there?

congrats! did you get an alignment after you installed your wheel spacers?