Poll on Transmission Flush at High Miles

[m5james]

Originally Posted by FSETH

If you read the links provided by JCL, he as well as two reputable BMW techs (Weasel and killcrap) give pretty good reasons why changing the fluid can have adverse affects. Especially at higher mileage when no previous services were performed.

Also, I read the poll wrong. There should be one less vote for "all good and no issues so far" and one more for "never changed and I am not going to".

I run a BMW repair place here in Boise, am I mince meat here? I said in my previous post, you are correct...key words being "can" and "no previous". So for those w/ no problems now, lower mileage, etc....do it now or suffer later. I can't say it enough...NO fluid is lifetime and I've had to clean some pretty nasty stuff of the magnets in the pan, which NEVER changing the fluid will just continue move around in the system and make worse if the magnets aren't holding whatever else is floating around.

[FSETH]

Originally Posted by m5james

I run a BMW repair place here in Boise, am I mince meat here?

No, never said that. Just included those two because they are currently techs at BMW dealerships.

Just pointing out to DoubleA that is is not ALWAYS beneficial.

I agree with you and others that for a new BMW I would probably change the fluid regularly and disregard BMW's lifetime guideline, but for older BMW's with original fluid, I would leave it be.

[Mikedd]

Originally Posted by m5james

I run a BMW repair place here in Boise, am I mince meat here? I said in my previous post, you are correct...key words being "can" and "no previous". So for those w/ no problems now, lower mileage, etc....do it now or suffer later. I can't say it enough...NO fluid is lifetime and I've had to clean some pretty nasty stuff of the magnets in the pan, which NEVER changing the fluid will just continue move around in the system and make worse if the magnets aren't holding whatever else is floating around.

This echoes what my indie says as well. I'm turning 92K and I will have this done in the new year along with gaskets etc.

[JCL]

Originally Posted by DoubleA

Flushing the tranny fluid when due can only be beneficial, unless you put some cheap or not recommended oil or perhaps you dont put the require amount. How in the world a tranny flush could destroy it ? Guys please wake up and get yourself a coffee before making assumption that make no sense at all.

See the links in post #9. A transmission flush is a frequent trigger for transmission failure in a transmission that is otherwise performing well. That is why several of us who have worked in shops and have done overhauls on transmissions won't do transmission flushes on our own vehicles, unless the fluid is burnt. That doesn't mean that we don't believe in preventative maintenance, just that changing the transmission fluid often introduces new problems. You can check the links on this board as well for this phenomenon. The posts usually start with "I can't believe my bad luck, I just changed my transmission fluid and now my transmission has failed even though...." The transmission shops know all about this, it isn't in any way a secret.

[Mikedd]

Originally Posted by JCL

See the links in post #9. A transmission flush is a frequent trigger for transmission failure in a transmission that is otherwise performing well. That is why several of us who have worked in shops and have done overhauls on transmissions won't do transmission flushes on our own vehicles, unless the fluid is burnt. That doesn't mean that we don't believe in preventative maintenance, just that changing the transmission fluid often introduces new problems. You can check the links on this board as well for this phenomenon. The posts usually start with "I can't believe my bad luck, I just changed my transmission fluid and now my transmission has failed even though...." The transmission shops know all about this, it isn't in any way a secret.

That quote is exactly what we are trying to determine in our own un scientific way. My Indie with 25 years on BMW swears that he has never seen a transmission fail from a fluid change (That wasn't shot to begin with). Poll so far (small sample) indicates that no one has had their high mileage tranny fail with fluid change? More responses would be good. Now watch, I,m going to flush and drop the pan next week and the tranny will fall out on Christmas day!

[m5james]

The problem is people wait too long before they change the tranny fluid. NO fluid is lifetime, NONE...not even ZF's mythical Esso. 4 personally owned BMW's (countless customers cars that I've done), every 50k like clockwork, never a failed tranny yet...period. It's all nothing but opinions out there about the people results of changing fluid, but we never know how the tranny was treated by each individual user.

What most don't consider is that maybe it was already failing because they abused it - stop light racing everytime, Reverse to Drive w/o coming to a complete stop, hard driving on a cold engine instead of letting the engine AND tranny get to temperate via driving slowly AT THE SAME TIME (aka garage warmups that turn into immediate hard driving while the tranny is still cold). Most people wait until they get the slamming hard shifting before they address the problem. I personally am for preventative maintenance and don't believe in the "If it isn't broke don't fix it" mentality. Regardless of various peoples driving habits, personal maintenance beliefs, etc, one thing remains constant regardless of opinion...NO fluid is lifetime.

[m5james]

I was just looking at shipping options for this lump of coal...i'll save it for someone else

I agree that its not always for everyone, but more for preventative maintenance as opposed to those w/ hard shifting issues looking for a fix, because by then it probably is too late. When I had my supercharged 01 Tacoma V6 (traded for the 7), there were many discussions then about flushing fluid if the trans was shifting hard. There was a general consensus then also that basically it was a lack of maintenance and it was too late, and that changing the fluid would somehow speed up the failure. I'm sure BMW's, or any tranny for that matter, is no different. Change the fluid before it becomes a problem, don't wait till you've got issues then expect an $80 fluid change to make miracles happen...the damage has already been done at that point.

I'd imagine all those little pieces of metal wash all around the transmission, slowly polishing away the checkballs and oil passages just like Extrude honing does to heads and intake manifolds. The passages get gouges, check balls allow too much fluid past, the fluid loses it flow characteristics since it's essentially contaminated = hardshifting. Hell, engines get the same damage due to lack of oil changes...scoring of the cylinder walls, clogged passages, etc. Changing the fluid to remove those metal particles before they do their damage prevents (or at least slows) that damaging process. The magnets holding those particles can only do so much, and they lose their efficieny to continue holding more and more particles as they get more and more built up. I've got pics on my website of a few tranny pans I've dropped, and those magnets were CAKED w/ fine grit and 1 w/ a sizeable chunk that shouldn't have been there

[RDAvena]

Dropped the pan and replaced filter and fluids.

68,000 Miles
Amsoil AFT used and I had the same moss growing on my magnets as the one above. Scratched off that "Lifetime" sticker and added an extra rare earth magnet to the pan just in case. At 110,000 now and no issues. Spirited driving, manual shifting, etc. At 125,000 I will do the same.

When the bean counters start doing engineering work that is when parts fail.

[m5james]

Originally Posted by RDAvena

Dropped the pan and replaced filter and fluids.

68,000 Miles
Amsoil AFT used and I had the same moss growing on my magnets as the one above. Scratched off that "Lifetime" sticker and added an extra rare earth magnet to the pan just in case. At 110,000 now and no issues. Spirited driving, manual shifting, etc. At 125,000 I will do the same.

When the bean counters start doing engineering work that is when parts fail.

I completely agree about the bean counters

For fluid, people have had success over the years also using Castrol Import Multi-Vehicle (dino oil) and Valvoline MaxLife (Synthetic). Its also been shown that the only difference between a normal Dexron III and Esso is the extra additive Esso uses to extend the servicing intervals. I'd rather save my $3k transmission by spending $80 in fluids and change it every 50k instead of letting the bean counters and engineers use me as a guinnea pig. I've read countless stories of failing trannies due to lack of maintenance and/or following BMW suggestions, but I have yet to read (or personally experience w/ my own cars) about a failed tranny due to "over" maintenace by not following their recommendations. Everyone can do what they want, but I know what's worked for me since my 1st BMW purchase in 98 when I read these same stories back then.

[JCL]

Originally Posted by RDAvena

Dropped the pan and replaced filter and fluids. 68,000 Miles. Amsoil AFT used and I had the same moss growing on my magnets as the one above. Scratched off that "Lifetime" sticker and added an extra rare earth magnet to the pan just in case.

The metal particles aren't what will bite you, it is the material from the clutch packs and bands. That material isn't metallic. It is what usually is dislodged when the fluid is changed. Anything large enough to settle in the pan is large enough to be caught by the filter, in general terms. I agree it looks bad in photos of a transmission pan, but it isn't like it is hurting anything.