OK I did transmission fluid flush on my 02 4.4i

[sunny5280]

Originally Posted by Vonbimmer

I have been watching the outcomes of transmission fluid changes here since 06' and JCL is right on target. The post change failure rate is just high enough to make the process too risksy to be worth pursuing. Add to that, that the dealer won't do it to make a buck and I'm sold on it being a bad idea.

You've been watching it? How have you been watching it? What does "watching it" mean?

[TwinTurboGTR]

Originally Posted by sunny5280

Consensus doesn't prove anything. I'm in the camp of changing the transmission fluid. I had it changed in my 2001 4.4i with 108K miles (right after I purchased the vehicle) and drove it to 129K miles before buying my current X5. Never had a hint of problem with it.

Consensus is always composed as a matter of opinion. Looking through threads, many on here have experiences problems after a fluid change, i.e. Trans fluid is a high detergent fluid, after a change, dislodges debris within the tranny. The debris could clog up passages for the fluid to circulate, starving the tranny of fluid in critical places. Is it 100%? No... it doesn't always happen and I am sure those who have changed their tranny fluid have experienced many miles of trouble free service and really don't voice the success. But those who have changed the fluid and experience failure, you can bet that they will always broadcast it.

While I agree fluid changes are necessary... I do not agree with having to spend a few hundred to change the fluid on a working transmission, then experiencing a failure and spending a few grand to fix it. Again, matter of opinion. If it ain't broke, don't fix it.

[JCL]

Originally Posted by sunny5280

Consensus doesn't prove anything.

Completely agree.

But I would respectfully point out that consensus implies a large sample, and you are holding your example out as proof to the contrary, in a case where n=1.

I would not expect you to have had a problem after changing your fluid, as more transmission will be fine post fluid change than will fail. But we are discussing the risk of failure, statistically, not whether they will all fail. And on the other side of the coin, you don't know that your transmission wouldn't still be running fine with the original fluid. You spent the money, got no return on that investment, and arguably increased your risk. Is that an investment decision you recommend all should make?

[sunny5280]

Originally Posted by TwinTurboGTR

Consensus is always composed as a matter of opinion. Looking through threads, many on here have experiences problems after a fluid change, i.e. Trans fluid is a high detergent fluid, after a change, dislodges debris within the tranny. The debris could clog up passages for the fluid to circulate, starving the tranny of fluid in critical places. Is it 100%? No... it doesn't always happen and I am sure those who have changed their tranny fluid have experienced many miles of trouble free service and really don't voice the success. But those who have changed the fluid and experience failure, you can bet that they will always broadcast it.

While I agree fluid changes are necessary... I do not agree with having to spend a few hundred to change the fluid on a working transmission, then experiencing a failure and spending a few grand to fix it. Again, matter of opinion. If it ain't broke, don't fix it.

In theory the explanation makes sense. However there have been nothing but anecdotes to support such a thoery. We don't know all the details that go into each anecdote. For example it's not unlikely someone was experiencing a transmission issue and decided to try changing the fluid in an effort to correct it. Instead masking an underlying problem. Until there is support data it remains nothing more than theory.

[sunny5280]

Originally Posted by JCL

Completely agree.

But I would respectfully point out that consensus implies a large sample, and you are holding your example out as proof to the contrary, in a case where n=1.

I would not expect you to have had a problem after changing your fluid, as more transmission will be fine post fluid change than will fail. But we are discussing the risk of failure, statistically, not whether they will all fail. And on the other side of the coin, you don't know that your transmission wouldn't still be running fine with the original fluid. You spent the money, got no return on that investment, and arguably increased your risk. Is that an investment decision you recommend all should make?

No, I am holding the 25+ years of experience of my indy mechanic as evidence. As I said he worked for a local BMW dealer for 25+ years. In his experience he has not observed any correlation between changing the fluid and subsequent failure.

Likewise I have seen no supporting data anywhere to support this theory. If you've got some hard data I will be happy to take a look at it and reconsider. Until such time all we have are a number of anecdotes that form the "consensus". There could be any number of reasons for why a transmission failed after a fluid change. The most obvious being it was done incorrectly (which could be reason enoug to avoid doing it). It's not uncommon for work to be performed in an incorrect manner with problems as a result.

[JCL]

Originally Posted by sunny5280

No, I am holding the 25+ years of experience of my indy mechanic as evidence. As I said he worked for a local BMW dealer for 25+ years. In his experience he has not observed any correlation between changing the fluid and subsequent failure.

Likewise I have seen no supporting data anywhere to support this theory. If you've got some hard data I will be happy to take a look at it and reconsider. Until such time all we have are a number of anecdotes that form the "consensus". There could be any number of reasons for why a transmission failed after a fluid change. The most obvious being it was done incorrectly (which could be reason enoug to avoid doing it). It's not uncommon for work to be performed in an incorrect manner with problems as a result.

We've had this discussion many times before Sunny, and I am not out to change your mind. You have your mind made up. Fair enough. All of the posts that we provided to you documenting transmission failures post fluid change on past threads, you discounted as "probably a coincidence" and "anecdotal".

The outstanding question is, didn't you have to replace your own transmission valve body? You posted and described that in some detail back when it happened. I remember the references to your trusted independent mechanic, and a thread about your own transmission fluid change. I can't link to those discussions, because unfortunately the threads were subsequently edited. Perhaps they were leading to reader confusion about coincidences and anecdotes.

Any comment?

[sunny5280]

Originally Posted by JCL

We've had this discussion many times before Sunny, and I am not out to change your mind. You have your mind made up. Fair enough. All of the posts that we provided to you documenting transmission failures post fluid change on past threads, you discounted as "probably a coincidence" and "anecdotal".

Why would I change my mind when the facts haven't changed? The facts are there is not supporting data for this theory. I've requested it numerous times and each time it has never been provided. Anecdotal stories, and that's what they are, posted on a forum is not supporting data. Not trying to be a jerk about this but I have a mechanic with over 25+ years experience working at a BMW dealership in various service capacities who tells me otherwise.

Originally Posted by JCL

The outstanding question is, didn't you have to replace your own transmission valve body? You posted and described that in some detail back when it happened. I remember the references to your trusted independent mechanic, and a thread about your own transmission fluid change. I can't link to those discussions, because unfortunately the threads were subsequently edited. Perhaps they were leading to reader confusion about coincidences and anecdotes.

Any comment?

I'd appreciate it if you'd keep any implications editing of posts was done to deceive others. Typically I edit a post to correct spelling / grammar errors or to rephrase a thought after I've gone back and re-read it after posting.

With that said I owned two E53 X5's. The first, a 2000 with 85K miles required the valve body to be replaced. The second, a 2001 with 108K miles on it when I purchased it, had ALL the fluids replaced when I purchased it.

You can find the first mention of the 2000 issue here:

http://www.xoutpost.com/728325-post15.html

And the first mention of the 2001 transmission fluid replacement here:

http://www.xoutpost.com/756050-post3.html

And look...neither of them show as having been edited.

[TwinTurboGTR]

Originally Posted by sunny5280

Why would I change my mind when the facts haven't changed? The facts are there is not supporting data for this theory. I've requested it numerous times and each time it has never been provided. Anecdotal stories, and that's what they are, posted on a forum is not supporting data. Not trying to be a jerk about this but I have a mechanic with over 25+ years experience working at a BMW dealership in various service capacities who tells me otherwise.

No one has asked for you to change your mind and no one is trying to convince you otherwise. Your opinion is your opinion and you are welcome to it. From what FORUM readers and FORUM techs have said, yes, doing a tranny fluid change on a worked out tranny heightens the risk of transmission damage. For your tech with 25+ years experience to tell you other wise is completely fine. But I will reverse your logic. You coming to the forum and telling us there is no substantial data to support the theory that a fluid change could possibly result in a failed tranny and that you have never seen supporting data is fine. Techs with years of experience have mentioned that this is possible and is a relevant concern. But... we haven't seen any data you have provided from your tech with 25+ years experience that proves the complete opposite. Supporting date could be an excel sheet listing all of the trannys he has done a fluid change on and how many have come back to thank him after another 50K, 75K, 100K miles of service and do another fluid change.

The point JCL and I were trying to make was, it IS possible to damage a transmission by doing a fluid exchange. We have seen it happen on the forum and I am sure JCL has seen it during his career personally. The statements you have made pertaining to your tech sound like absolute statements (Fluid changes do not cause transmission failures). And if your tech is saying that, then fine, we would actually love to hear that because it would stop the madness about doing and not doing a change of fluid and will give us a definitive answer. But until you can prove it, then its all relevant. There are forum members that have done a fluid change without any problems. Some have even used fluid that isn't even the spec it calls for and they are still fine. Bust some have had the service done at their shop or at the dealer and they have come back with a trashed tranny.

On another note, thats great your tech has had numerous roles, is a shop owner, and is 25+ years in. Thats really great and is probably a wealth of knowledge. But in my honest opinion... the power of the forum is better than any tech on his own. A forum is a collaboration of tried and true methods, fixes, and symptom hunting. I mean there have been countless times when members have come to the forum describing a symptom that their tech or dealer couldn't figure out, and 9 times out of 10 we've come up with the right solution. There is information on here that some dealerships haven't even heard of, "i.e. TSB numbers, tricks, tips, etc" Heck, members have even designed and manufactured their own parts that are better than original. So before regarding information on forums as mere heresay, you might want to add in your own "one hitter quitter" to back up your own claim. JCL and I have seen it many times on the forum here. We've witnessed heated arguments going back and forth between the advantages, disadvantages, turmoils, which fluid to use, etc. Information that you mentioned you have seen. Well, we haven't seen any of yours...

Again, not going meaning this to challenge you, or get into an argument, or the flame each other. But... just sayin...

[sunny5280]

Originally Posted by TwinTurboGTR

No one has asked for you to change your mind and no one is trying to convince you otherwise. Your opinion is your opinion and you are welcome to it. From what FORUM readers and FORUM techs have said, yes, doing a tranny fluid change on a worked out tranny heightens the risk of transmission damage. For your tech with 25+ years experience to tell you other wise is completely fine. But I will reverse your logic. You coming to the forum and telling us there is no substantial data to support the theory that a fluid change could possibly result in a failed tranny and that you have never seen supporting data is fine. Techs with years of experience have mentioned that this is possible and is a relevant concern. But... we haven't seen any data you have provided from your tech with 25+ years experience that proves the complete opposite. Supporting date could be an excel sheet listing all of the trannys he has done a fluid change on and how many have come back to thank him after another 50K, 75K, 100K miles of service and do another fluid change.

I don't have to. The burden of proof for a theory rest solely on the shoulders of those making it.

Originally Posted by TwinTurboGTR

The point JCL and I were trying to make was, it IS possible to damage a transmission by doing a fluid exchange. We have seen it happen on the forum and I am sure JCL has seen it during his career personally.

Anything is possible. All I ask is for you to support your theory with data. Not anecdotes from forum members where the details of the situation are varied and largely unknown.

Originally Posted by TwinTurboGTR

The statements you have made pertaining to your tech sound like absolute statements (Fluid changes do not cause transmission failures). And if your tech is saying that, then fine, we would actually love to hear that because it would stop the madness about doing and not doing a change of fluid and will give us a definitive answer. But until you can prove it, then its all relevant.

I don't have to prove anything. The burden of proof lies on those making the claim changing the fluid can lead to problems. I'm receptive to that theory and merely ask for supporting data, not anecdotes.

Originally Posted by TwinTurboGTR

There are forum members that have done a fluid change without any problems. Some have even used fluid that isn't even the spec it calls for and they are still fine. Bust some have had the service done at their shop or at the dealer and they have come back with a trashed tranny.

The fallacy being the transmission fluid change was the cause of the trashed tranny. Until data supporting the cause of the failure was related to changing the transmission fluid is provided it could merely be coincidence. Or, and this seems more plausible, the fluid change was done incorrectly.

Originally Posted by TwinTurboGTR

On another note, thats great your tech has had numerous roles, is a shop owner, and is 25+ years in. Thats really great and is probably a wealth of knowledge. But in my honest opinion... the power of the forum is better than any tech on his own. A forum is a collaboration of tried and true methods, fixes, and symptom hunting. I mean there have been countless times when members have come to the forum describing a symptom that their tech or dealer couldn't figure out, and 9 times out of 10 we've come up with the right solution. There is information on here that some dealerships haven't even heard of, "i.e. TSB numbers, tricks, tips, etc" Heck, members have even designed and manufactured their own parts that are better than original. So before regarding information on forums as mere heresay, you might want to add in your own "one hitter quitter" to back up your own claim. JCL and I have seen it many times on the forum here. We've witnessed heated arguments going back and forth between the advantages, disadvantages, turmoils, which fluid to use, etc. Information that you mentioned you have seen. Well, we haven't seen any of yours...

My tech is now the owner of his own business. While he does work on vehicles from time to time he has other people doing the work for him. Where his 25 + years experience comes into play is having worked at a BMW dealership. He's seen more than his fair share of BMW vehicles prior to starting his own business.

Originally Posted by TwinTurboGTR

Again, not going meaning this to challenge you, or get into an argument, or the flame each other. But... just sayin...

Say what you will. My participation in this thread was not to argue the merits of changing the transmission fluid or not. It was to state that having a consensus doesn't really mean much without supporting data. After all at one time the consensus was the earth was flat.

[TwinTurboGTR]

Ok, seems like we are getting no where. You've made your own claims that a fluid change WILL NOT cause damage to a transmission. And again thats fine. But if you are asking us to prove it, then you will have to as well. Otherwise, again, all heresay. So what I am asking is for your proof. Again, this is supposed to be a discussion and so far, its one sided.

But you'll probably come back and say "I don't need to provide proof" Well, thats fine. Our proof is from members that have explained the situation in detail. Also from techs explaining it in great detail (BMW techs and indy's). So sounds like this thread is dead. You want to provide YOUR proof, we welcome it. If not, then I guess your information is heresay, much like ours.