Does Changing Lifetime Fluid Kill Transmissions?

[Cambridge]

I am thinking about changing the lifetime fluid in my 5hp30. It has never been changed before. Unfortunately, my 540i has 114,000 miles on it.

Everyone says that I should have started changing the fluid every 50-75,000 miles back when the car only had 50 - 75,000 miles on it (unfortunately I didn't own the car back then).

Some say it's too late to start now. (I've heard several reasons, e.g. detergent will disolve the adhesive holding the clutch friction pads or the act of draining the fluid will force junk into the valve body causing problems there, etc, etc.)

Others say, start changing it now and hope for the best - life's a risk.

Hence, my poll. I'd like to know how many who started changing their fluid after 100,000 miles had cars that survived the change for 1000 miles, 5000 miles, 10000 miles.

BTW: when I say "change" it means by whatever procedure you use to get fluid in and out of the tranny. e.g. some just replace the fluid in the pan, others let the car sit overnight or have other methods of extracting as much fluid as possible with each change. This poll is not to study the method of fluid change, rather it is to determine the fatality rate on lifetime fluid transmissions when fluid service starts late in life - by whatever form that service takes.

[632 Regal]

you need to change your poll, the proper way to change it is only drain the pan and change just what comes out and put in a new filter. This is supposed to be done every 30k. I was told this by Kirt Kohller a couple years ago. He also added to never flush it all out and change it, re adding the old crap (appx 4 qts) is ok but new is better.

[mattyb]

is it ok to just leave it in there and never change it as advised by bmw?

[632 Regal]

No. Lifetime means 100k then the car is disposable.

is it ok to just leave it in there and never change it as advised by bmw?

[Cambridge]

is it ok to just leave it in there and never change it as advised by bmw?

Seems best to change it despite what BMW says. I'd say the majority of posts lean that way. There are a few that say the tranny will wear out, regardless, at 100 - 150,000 miles anyway. But again, those are few. Most are hoping to get the most mileage by having a regular program of service.

Indeed many of us, if we had purchased our cars new, would have done the "right" thing and regularly serviced our transmissions. Unfortunatly, many of us acquire our E34's later in their life after 100,000 miles or so of no service.

Hence some of us wonder, will we make matters worse and shorten tranny life by starting a fluid service program now rather than letting matters run their course?

Thus, the poll is trying to find how many went ahead and started servicing their tranny's late in life and were successful.

[swenpro]

I too am interested in hearing more from those who had FIRST-HAND EXPERIENCE with changing automatic transmission fluid...

I've never changed it and am approaching 100k soon! (I too experience notorious *clunk* shift btw 2nd and 3rd when tranny is warm )

You're stories, please! thanks

[Cambridge]

Currently showing a failure rate of 1 out of 5 - not a very large sample. So far doesn't look like many have had first-hand experience at this.

[Cambridge]

Failure rate is now 1 out of 4 - this isn't heading in the right direction...

[Maki]

It's a shame that none of the people who experienced transmission failure after changing fluid with high miles posted their experiences in more detail. Were the cars driven extensively in city traffic? Did they tow anything? What kind of climate were they in? Was the change DiY or at a BMW dealership? I'd be interested in knowing the cars' histories leading up to tranny death.

[Cambridge]

It's a shame that none of the people who experienced transmission failure after changing fluid with high miles posted their experiences in more detail. Were the cars driven extensively in city traffic? Did they tow anything? What kind of climate were they in? Was the change DiY or at a BMW dealership? I'd be interested in knowing the cars' histories leading up to tranny death.

the reason why the tranny's died. ...maybe I need to design another poll?