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

[sunny5280]

Originally Posted by faz

I actually read through almost all of this thread.

This is a really good thread, in that, anyone who doesn't have a firm opinion on whether they should or should not change their transmission fluid (especially at a high mileage), ... who ends up finding this thread through a search and reads through this thread.... will most definitely NOT change the transmission fluid, based on the materials presented by both sides AND the manner in which they were presented.

Then they would being doing so against sound advice and favoring an urban legend.

[Penguin]

Originally Posted by sunny5280

Then they would being doing so against sound advice and favoring an urban legend.

Well, I probably should just drop this, but why is that any more of an "Urban Legend" than the "Urban Legend" that changing your AFT will make your transmission last longer?

I guess I am saying that the term "Urban Legend" is a bit strong and misleading in that context. I would position it more as "debatable and supported only through anecdotal reports, which are not statistically significant."

Which could also be said of the other side of the argument.

P.S. I promise to shut-up about this topic after this post.

[sunny5280]

Originally Posted by Penguin

Well, I probably should just drop this, but why is that any more of an "Urban Legend" than the "Urban Legend" that changing your AFT will make your transmission last longer?

Arguments pro "change the ATF":

• BMW recommends it at 100K mile intervals.
• No fluid is lifetime. Lifetime being defined as never change.
• Fluids act as a detergent and become dirty with use.
• The protective qualities of lubricants breaks down over time.
• Every other fluid in the vehicle is subject to change at regular intervals.
• Other vehicle manufacturers recommend ATF changes.

Arguments con "change the ATF":

• In 2002 Mike Miller, head technical editor of BMWCCA, made the recommendation to avoid ATF changes due to his observed increase in subsequent transmission failures.
• Numerous web sites making the same recommendation as Mr. Miller.

So we have facts for pro "change the ATF" (I put this in quotes because my argument has never been to change the ATF but more it doesn't hurt to do it) and opinions on the con "change the ATF".

In 2009 Mr.Miller appears to have reevaluated his 2002 recommendation and no longer has the passion for it he once had (but does continue to say there is a risk). As for the numerous web sites I suspect they picked up on Mr. Millers 2002 recommendation and ran with it. And now discussions on this subject make references to one another (it happened in this one) in a form of circular support (I've seen this happen too many times).

Many disagree with my urban legend label but that's how I view it. An unsupported claim has been made and repeated ad infinitum and taken on a life of its own. So much so that people making it feel threatened when someone dare question it.

[JCL]

Originally Posted by sunny5280

Arguments pro "change the ATF":

• BMW recommends it at 100K mile intervals. Which coincidentally, is when your warranty is over. They don't want you changing it during the warranty period. Once that is over, any failure is at your risk. Of course, they would never be that calculating.
• No fluid is lifetime. Lifetime being defined as never change. This is a position, not an argument.
• Fluids act as a detergent and become dirty with use. Actually, the ATF includes detergent additives. When those additives are all gone, it would be a reasonable time to change the fluid. The fluid gets dirty, but that is why there is a filter.
• The protective qualities of lubricants breaks down over time. Well, oil never stops being slippery, the lubrication qualities never fade away. The fluid does need to be incompressible (to work the actuators), and to be a heat conductor. There are additives to prevent foaming, and friction modifiers for the clutches. So, if the additives are depleted, the fluid could benefit from being changed. However, those very high mileage transmission being reported (on original fluid) suggest that the additives do in fact last a very long time. Perhaps even the component's lifetime.
• Every other fluid in the vehicle is subject to change at regular intervals.How about your AC refrigerant (which lubricates the compressor), or the grease in the CV joints. They are lifetime too. I suggested shock absorbers before, but that got shot down. How about universal joints? Tie rod ends? Ball joints? Steering shafts? All things that used to be lubricated before we went to lifetime lubrication. There are not many places to use a grease gun on a modern vehicle any more.
• Other vehicle manufacturers recommend ATF changes. That would be a good reason to follow their recommendations, to keep your warranty valid. But aren't we talking about BMWs here?

Arguments con "change the ATF":

• In 2002 Mike Miller, head technical editor of BMWCCA, made the recommendation to avoid ATF changes due to his observed increase in subsequent transmission failures.
• Numerous web sites making the same recommendation as Mr. Miller.
• Numerous mechanics and BMW technicians making the same recommendation.

Comments included above in red.

I should clarify that I don't necessarily think that ATF should never be changed, or that it should always be changed. I do think that readers should make their minds up after understanding the risks and rewards. There is no conclusive data either way. There are reasons to change the fluid, and reasons not to. Readers making an informed decision after understanding the two sides is far better than blindly changing it because it is somehow supposed to be done.

[sunny5280]

Originally Posted by JCL

Comments included above in red.

My responses in blue.

Originally Posted by JCL

I should clarify that I don't necessarily think that ATF should never be changed, or that it should always be changed. I do think that readers should make their minds up after understanding the risks and rewards.

It seems we've been agreement the entire time.

Originally Posted by JCL

There is no conclusive data either way.

Yet the con "change ATF" people act as if there is. My position is, and always has been, there's no data to show a correlation between changing the ATF fluid and subsequent transmission failures. Therefore it's an urban legend, folklore, wives tale, what-have-you.

[JCL]

Originally Posted by sunny5280

My responses in blue. And mine in red - JCL

• Irrelevant. They're recommending the fluid be changed. You're not implying they're recommending a service which offers no benefit or runs an excessive risk of damaing the vehicle are you? Of course not, that would be slanderous. I am pointing out that since owners want a mileage figure for the fluid change, for a procedure with no defined benefit, and some potential downside, that BMW would like you to do it after the warranty is over so as not to cause them to have to pay for your transmission. Or it could be a coincidence.
• It is a fact thus making it an argument. I wish I could be as sure of anything as you are. Note this one for later.
• Therefore changing the fluid restores those lost qualities the fluid offers. So how do you know the additives are worn out? You are ignoring the evidence we do have that they last much longer than that.
• Perhaps? Suggest? Not confidence inspiring. I find that speaking in absolutes leaves one open for ridicule. Ever find that?
• Yes these items wear and eventually require replacement. Those were lifetime fluids in those items. You earlier said there is no such thing as a lifetime fluid. You even called that statement a fact, not an opinion. Do you see the weakness in your argument here?

It seems we've been agreement the entire time. No, we're not. You are so sure of yourself that you miss the logical inconsistencies in your position.


Yet the con "change ATF" people act as if there is. My position is, and always has been, there's no data to show a correlation between changing the ATF fluid and subsequent transmission failures. Therefore it's an urban legend, folklore, wives tale, what-have-you. And that is why we haven't been in agreement. You, one of the "pro change ATF people" act as if there is correlation between changing the fluid and longer transmission life. You refuse to acknowledge that there are both risks and rewards, and you discount the risks while reaching for the potential rewards. I think you coined it "urban legend vs sound advice"

Others have noted that your continued use of the phrase 'urban legend' is somewhat misleading. I agree with this observation. It is an urban legend to you because you have never seen it, and are not familiar with the workings of an automatic transmission. If I have seen examples firsthand that persuade me that there is a risk that outweighs the rewards, and at the same time I don't even know who Mr. Miller is but rather rely on my own experiences, it doesn't feel like an urban legend. Anecdotal, perhaps. However, many things in life are based on professional judgement, as opposed to internet heresay.

MD was correct in that this is a little like a high school debate. The purpose of it to me, though, is to show both sides of the argument, so that future readers can make their own minds up and not rely on the old wives tale/urban legend/etc that all fluids are worn out soon after being installed. I think we are probably accomplishing that.

[FSETH]

Originally Posted by JCL

MD was correct in that this is a little like a high school debate. The purpose of it to me, though, is to show both sides of the argument, so that future readers can make their own minds up and not rely on the old wives tale/urban legend/etc that all fluids are worn out soon after being installed. I think we are probably accomplishing that.

As anyone can see from my first post in this thread where all I was trying to do was let people know there are possible risks. I personally think it is worth letting people know. Like I said, I didn't realize this myself until shortly after buying our X in 2007.