OK I did transmission fluid flush on my 02 4.4i

[JCL]

Originally Posted by e30cabrio

I am interested in the argument against replacing old fluids that no longer provide protection.

Can someone please explain how it is better to leave it in than possibly dislodge unknown contaminants that may or may not be in the system.

Sure. Transmission fluid is designed to last a long time. It is in a sealed system, so it doesn't get contaminated by things like engine oil does. It has additives that fight oxidation, and foaming. There are also friction modifiers. Over time those additives become depleted. The fluid does wear out over a long enough period of time. It doesn't stop lubricating, but it does lose some specific properties. Recall that lubrication is the lowest requirement of a transmission fluid. It is a very undemanding lubrication requirement. That is why it is a straight 10w oil. It is primarily a hydraulic fluid. The question is, does it wear out before the transmission expires of other, unrelated causes? Most failures we are seeing are related to things not related to lubrication (wiring harnesses, sensors, etc). Those failures won't be impacted by a fluid change. So, there is a big question as to whether changing the fluid will have any effect on average transmission life.

Now, what happens when a transmission wears (naturally) over time? There are sediments created by clutch plate material, generally non-metallic, and they sit in the pan on the dirty side of the filter. Not the clean side. They look bad, but they don't hurt anything. They are also distributed throughout the transmission. There, again, they usually don't hurt anything. Now put in new fluid. Very high detergent levels, by design, that is what makes it last so long. Those detergents clean out the transmission. Same reason we use ATF in an engine to clean out combustion deposits. What happens when those deposits are loosened? They go through the transmission. They end up in the valve body. If they make it to the pan, no problem. If they get stuck in the valve body, in a sensor, in an actuator, etc, they can cause an early transmission failure. It happens. Not always, but often enough to show up in the statistics.

So the debate is, is the risk of damage (lets call it x) greater than y (the benefit of clean fluid, which is generally a good thing). If you believe that clean fluid is such a benefit that it overshadows the risk of failure through introducing new fluid, then change it. If you acknowledge the risk (small on a total population basis, but real) and don't see a history of failures due to aged fluid then you would not change it, save the money, and put it aside for an eventual transmission rebuilt not caused by a fluid issue.

There isn't a right answer. The only error, IMO, is not acknowledging that there is some risk, and that there is no demonstrated benefit. This isn't to say that all preventative maintenance is bad. It is usually good. But where there isn't a correlation between PM activities and extended component life, then it is better and cheaper to run it to failure. That is counterintuitive to some.

Hope that helps.

[e30cabrio]

Thanks for taking the time to give me that info.

My transmission is fine currently. I guess I'll leave it alone for now and just do the rest of the fluids (already did the power steering).

[JCL]

Originally Posted by sunny5280

I didn't say you did. I said, and I quote:

"If you've got an accusation I've been deceitful through editing my posts then say it..."

Fine. I didn't say it. You suggested I implied it. That better? For the record, I didn't imply it either. I simply noted that back when the previous discussion was going on, there was editing happening. It made it hard to follow the discussion at the time. The reason I remember is, there was at least one side conversation going on on private messages, with dicussion and comments about your approach. You were engaging in a debate with half a dozen or so forum regulars, some of whom had trouble following your logic. It just stuck in my mind.

Originally Posted by sunny5280

Do you understand english? Is it not your native language?

Seriously? You want to insult every person who has English as a second language? Sí, Inglés es mi idioma principal. Sí, lo entiendo. Es la reparación de vehículos su primera profesión? No need to answer that.

Originally Posted by sunny5280

What does this mean? Do you mean that I was deleting posts? Where are the references? Specifics please.

Yes, it means you were deleting or modifying messages. Here is one specific example: See the thread http://www.xoutpost.com/bmw-sav-foru...nsmission.html. Your post #29. It was long. I wrote a detailed response. I had quoted you, so I had a copy of the long text. The flaw was that you used a circular argument in describing your burden of proof point. When I posted, I got a system error. It turned out that you had deleted the long text while I was typing, and left only a short response. Probably a good thing, because you had dug yourself a hole. My response in post #30 was my reminder. Is that all specific enough for you?


I have been thinking about something. Your reference for best practices on maintaining a BMW automatic transmission is an ex BMW dealer employee. Let's assume he knows all about BMWs. Now, how would he know anything about automatic transmissions built by ZF or GM? BMW doesn't train their dealer techs on those transmissions. They don't provide parts through their dealer system, so rebuilds are very unlikely at a dealer. Dealers are offered exchange transmissions in the event of transmission failures. And the BMW service instructions included in at least one case, instructions to drain the fluid and reinstall it, if a dealer tech had to go inside the pan. Yet an ex dealer employee is presented as an expert witness, so to speak. Doesn't seem like a logical conclusion.

[HPIA4v2]

Interesting, so the argument "don't flush trans fluid on hig mileage" argument really support "change the trann fluid more often, early" argument. Think about it...

[sunny5280]

Originally Posted by JCL

Fine. I didn't say it. You suggested I implied it.

I didn't suggest it. I said it:

"I'd appreciate it if you'd keep any implications editing of posts was done to deceive others."

Originally Posted by JCL

"That better? For the record, I didn't imply it either. I simply noted that back when the previous discussion was going on, there was editing happening.

That's an implication.

Originally Posted by JCL

It made it hard to follow the discussion at the time. The reason I remember is, there was at least one side conversation going on on private messages, with dicussion and comments about your approach. You were engaging in a debate with half a dozen or so forum regulars, some of whom had trouble following your logic. It just stuck in my mind.

You're going to have to provide proof I ever did such a thing. It's easy to say something but you need to back it up. I won't hold my breath. Thus far you've failed miserably when asked to provide proof. All you've offered is "trust me because I said it".

Originally Posted by JCL

Seriously? You want to insult every person who has English as a second language? Sí, Inglés es mi idioma principal. Sí, lo entiendo. Es la reparación de vehículos su primera profesión? No need to answer that.

How is what I wrote an insult? I asked you if you understood english and asked you if it was not your native language. I asked these questions because you appear to have a poor grasp on the language given you're having such a difficult time understand the simple concepts I've written. There's nothing insulting about that.

Originally Posted by JCL

Yes, it means you were deleting or modifying messages. Here is one specific example: See the thread http://www.xoutpost.com/bmw-sav-foru...nsmission.html. Your post #29. It was long. I wrote a detailed response. I had quoted you, so I had a copy of the long text. The flaw was that you used a circular argument in describing your burden of proof point. When I posted, I got a system error. It turned out that you had deleted the long text while I was typing, and left only a short response. Probably a good thing, because you had dug yourself a hole. My response in post #30 was my reminder. Is that all specific enough for you?

No, there's nothing there to support I had done any deleting / editing / modifying of my post to CYA. Again: Because I said so isn't proof. This seems to be a difficult concept for you.

Originally Posted by JCL

I have been thinking about something. Your reference for best practices on maintaining a BMW automatic transmission is an ex BMW dealer employee.

I am not referring to it as a best practice. Please do not put words in my mouth.

Originally Posted by JCL

Let's assume he knows all about BMWs. Now, how would he know anything about automatic transmissions built by ZF or GM? BMW doesn't train their dealer techs on those transmissions. They don't provide parts through their dealer system, so rebuilds are very unlikely at a dealer. Dealers are offered exchange transmissions in the event of transmission failures. And the BMW service instructions included in at least one case, instructions to drain the fluid and reinstall it, if a dealer tech had to go inside the pan. Yet an ex dealer employee is presented as an expert witness, so to speak. Doesn't seem like a logical conclusion.

The point being he has not observed a correlation between changing the transmission fluid and subsequent failures of those transmissions. This is not to say you should change it. Or that it's a best practices. Just merely if you do decide to do it there doesn't appear to be an increased risk of failure as a result. This is a very easy concept...why are you struggling with it?

With that said you can easily put this to rest by merely providing the requested information (i.e. reliable data supporting your point of view). I entered this discussion because TwinTurboGTR said:

"There is a consensus from other members and former techs on this forum that support you don't touch the tranny if it has hit 100k and has never been cracked open before."

It was not my intent to begin discussing this topic yet again. It was to merely say consensus doesn't prove anything. Ironically he also said:

"...the topic has been beaten to death."

Right before he said ...the consensus is... If it's been beaten to death there's obviously no consensus.

[SlickGT1]

Same old story, another new person.

JCL, are you sure our transmissions are sealed? What about that vent tube that runs all the way to the engine bay.

Whatever.

I changed my fluid at 70K miles. Not flush, but drain and fill. I had crap stuck in my solenoids at 80k miles, so that put in about 10q of new oil.

My Lexus GS430 came with a card in the maintenance manual to drain and fill transmission every 30k miles. It is a very rare occurrence for the Lexus trans to fail, but the cases where it does fail, people were clueless about the regular oil refresh it required.

Will I keep changing the oil in my X5. Yes I will. Is it possible it will fail, yes it is. But, in my case, I am not afraid to try. I also use the proper oil, ZF6, and use a computer to monitor the fluid fill temperature.

Is my transmission acting better? Yes it is. But that could be since I "maintained" it with new solenoids, new fluid (times 3), new seals, and removed the crap that was blocking my solenoids since the beginning.

[Ricky Bobby]

Came in here for knowledge, suddenly I found out I was in for some serious bizness:

[JCL]

Originally Posted by SlickGT1

Same old story, another new person.

JCL, are you sure our transmissions are sealed? What about that vent tube that runs all the way to the engine bay.

Whatever.

I changed my fluid at 70K miles. Not flush, but drain and fill. I had crap stuck in my solenoids at 80k miles, so that put in about 10q of new oil.

My Lexus GS430 came with a card in the maintenance manual to drain and fill transmission every 30k miles. It is a very rare occurrence for the Lexus trans to fail, but the cases where it does fail, people were clueless about the regular oil refresh it required.

Will I keep changing the oil in my X5. Yes I will. Is it possible it will fail, yes it is. But, in my case, I am not afraid to try. I also use the proper oil, ZF6, and use a computer to monitor the fluid fill temperature.

Is my transmission acting better? Yes it is. But that could be since I "maintained" it with new solenoids, new fluid (times 3), new seals, and removed the crap that was blocking my solenoids since the beginning.

By sealed I meant that it is unlike an engine, which has multiple sources of potential contamination of the oil. It isn't pressurized, so no it isn't completely sealed. One of the reasons to remove the fill tube going up to the engine bay (on other vehicles, not sure if BMW followed the same logic) was because leaving the dipstick out allowed contaminants to enter.

There is a possibility (not proof, just a likelihood) that the contaminants in your solenoids got there because the new fluid with the high detergent level loosened them and they travelled through the transmission, becoming lodged where they caused some problem. That is the standard complication that shows up following a fluid change. It doesn't always happen, and it doesn't always cause a problem. But that is the recognized failure mode, regardless. It is great if you got away with just the solenoids. And if you have gone any reasonable time from the fluid change, then it isn't likely to happen later, failures usually happened closer to the fluid change time. In my experience. Which isn't proof, as Sunny will want clarified.

[JCL]

Sunny:

The multi-quoting is getting difficult to follow. In one combined and relatively short post:

I never implied you were trying to deceive others. You are incorrect in that claim. I said it was difficult for me to follow it, because of the editing. The editing I witnessed myself. I provided you a time stamp if you have forgotten. I can't comment on whether others were deceived or confused. You would have to ask them. Some of them have posted their thoughts, but it is probably better if you ask them directly.

I don't have moderator privileges here, so I cannot undelete your messages or portions of messages and thus provide proof to you. Readers (other than you and I) are going to have to decide what to believe.

You wrote: "....you appear to have a poor grasp on the language given you're having such a difficult time understand the simple concepts I've written. There's nothing insulting about that." OK. Sounds insulting to me. Maybe the subtlety was lost in writing it.

The examples that I referred to in previous posts were from a shop I worked in, as you know. I previously explained to you that you can't have customer's and employee's names. I understand your request perfectly, I just won't play your game. You are anonymous here (at least to me, not sure about others), why would you expect real data? It isn't second hand info in my case, heard from a friend of a friend or read on a message board. It is from working on transmissions. It follows that since I was involved in working on those transmissions, that I know whether the transmission had pre-existing problems or not. I know if the correct fluid was used or not. And those examples, to the extent they exist, are not part of the data set under discussion. Your proof is a third hand reference to an anonymous mechanic who worked in a BMW dealership, where technicians typically aren't trained to fix transmissions. You say that I have to provide proof, but you don't (that is your particular strawman for this argument). Sorry. Again, readers are going to have to decide what to believe.

I disagree with you that a topic that has an apparent consensus cannot continue to be beaten to death. That is simply because consensus doesn't imply unanimity. I got that from my English language training, by the way. It only takes a few (or one persistent person) to continue to beat it.

Maybe we should go back to the famous "worst of the worst" thread and revisit whether the BMW driving experience is part of the feature set, and why can't BMWs be as reliable as Hondas for the same price? That was an entertaining one as well.

Have a nice day.

Jeff (Now less anonymous)

[Whitecat]

Originally Posted by SlickGT1

Same old story, another new person.

JCL, are you sure our transmissions are sealed? What about that vent tube that runs all the way to the engine bay.

Whatever.

I changed my fluid at 70K miles. Not flush, but drain and fill. I had crap stuck in my solenoids at 80k miles, so that put in about 10q of new oil.

My Lexus GS430 came with a card in the maintenance manual to drain and fill transmission every 30k miles. It is a very rare occurrence for the Lexus trans to fail, but the cases where it does fail, people were clueless about the regular oil refresh it required.

Will I keep changing the oil in my X5. Yes I will. Is it possible it will fail, yes it is. But, in my case, I am not afraid to try. I also use the proper oil, ZF6, and use a computer to monitor the fluid fill temperature.

Is my transmission acting better? Yes it is. But that could be since I "maintained" it with new solenoids, new fluid (times 3), new seals, and removed the crap that was blocking my solenoids since the beginning.

Thanks, is zf6 works for mine 4.4.i?