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

[FSETH]

Originally Posted by Penguin

Did BMW change their recommendation for AT fluid changes from Lifetime/never to 100,000 miles?

Yes, they sure did, but I am not positive when that was.

[X5 Meister]

I'd have to double check but I know that from 2002+ it was 100,000 miles and not lifetime.

Coolant change interval went from 4 years in 2003 to lifetime in 2004+.

Originally Posted by FSETH

Yes, they sure did, but I am not positive when that was.

[JCL]

Originally Posted by X5 Meister

I'd have to double check but I know that from 2002+ it was 100,000 miles and not lifetime.

Coolant change interval went from 4 years in 2003 to lifetime in 2004+.

Meister, some good detailed information in your posts above. One comment would be that BMW can't be said to be changing their recommendations (which implies that the same engine or transmission is under discussion) if in fact the components changed from year to year. Your note shows that different engines have different maintenance recommendations. It isn't all about extending the intervals, it is about optimizing the maintenance cost when considering risks and other factors. If BMW are providing different recommendations for different engines (in the same model year) then that implies to me that the marketing department is not simply saying don't maintain them, but that the engineering department is saying that in this case, with this usage profile, with this engine, do the following.....

For most components, changing the fluid has little downside. For coolant, I would do it every four years, as the only downside I see is the environmental impact of disposal of the used fluid. You aren't going to negatively impact the cooling system. You can get coolant tested, but that is probably more work than reasonable.

The tranmission is the only component that I wouldn't touch, and it is due to the risk, which I have seen the consequences of. I know that I called it slight (Sunny keeps reminding me) but it is still greater than the offsetting benefit in my mind.

If I had a 100,000 mile warranty, and a 100,000 mile fluid change interval recomendation from BMW, I certainly wouldn't give BMW cause to deny warranty (when I fully expect the trans to fail anyway) by touching it. It is very easy to tell if a transmission has been opened.

Yes, it is a thoroughly dead horse, but I suspect some people are still finding out new information.

[sunny5280]

Originally Posted by X5 Meister

I'd have to double check but I know that from 2002+ it was 100,000 miles and not lifetime.

I would like to hear JCL and other's explanation as to why BMW did this.

[X5 Meister]

This thread is beating a long dead horse, but perhaps it's still an interesting discussion with some very valuable information. Let me just interject a couple of my observations/concerns:

1. I think there is certainly some strong credibility in the don't change the fluid in a non-maintained transmission, the question is, just what constitutes a properly maintained transmission where one wouldn't be at risk, or at least significantly lesser risk, of dislodging sediment? IOW, what's the magic cut-off mileage or age? Regular 10,000 mile changes, 15,000 mile, 20,000 mile, yearly, etc? With this I think I'd be more interested in hearing from ZF than BMW.

2. Given that BMW specifically states lifetime fill on the transmission, one concern I might have is that if I did change the fluid, and something went wrong with the transmission, would they cover it under warranty since they specifically said not to mess with it?

3. Not to add a 3rd component into the mix (engine oil, transmission fluid, and now...) but beginning 2004 model year BMW suddenly went to lifetime fill for the cooling system. Marketing decision? Does it fall under the same circumstances as transmission maintenance, etc?

4. While BMW seems to be gradually moving to completely maintenance free cars (at least on paper, especially when you are on a 3 year lease!) it appears that as newer engines come into play they are stepping up some maintenance schedules. Here is an interesting list of the 2011 model year maintenance schedules just as an FYI...

For the 335is (Coupe and Convertible), Z4 sDrive35is, and 740i/Li with the N54T engine:

• There is no 1200 Mile Service.
• Engine oil is the same as for the 335i (recommended: BMW High Performance 5W-30 Synthetic oil P/N 07 51 0 017 866)
• Spark plug replacement interval is 45,000 miles or at every 3rd engine oil service.
• Engine air filter replacement interval is at every 2nd engine oil change.

For the 135i (all versions), 335i (all versions), and 535i with the N55 engine:

• Spark plug replacement interval is 60,000 miles or at every 4th engine oil service.
• Engine air filter replacement interval is at every 2nd engine oil change.

BMW ALPINA B7:

• There is no 1200 Mile Service.
• Spark plug replacement interval is 30,000 miles or at every 2nd engine oil service.
• Engine air filter replacement interval is at every 2nd engine oil change.

Vehicle check: Check the expiration date on the M Mobility System sealant bottle. Change the bottle if needed.

ActiveHybrid 7: Maintenance is comparable to a 750i.

Spark Plug Replacement Intervals

2011 Model Engine Interval (miles); coincides with every _ Engine Oil change

128i, 328i, Z4 sDrive30i N52TU 60,000; 4th

135i, 335i, 535i N55 60,000; 4th

Z4 sDrive35i N54 45,000; 3rd

335is, Z4 sDrive35is, 740i N54T 45,000; 3rd

M3 S65 37,500; 3rd (first oil change is at 1200 miles)

550i, 750i, ActiveHybrid 7 N63 60,000; 4th

760Li N73 60,000; 4th

BMW ALPINA B7 N63B44M1 30,000; 2nd

[FSETH]

Originally Posted by X5 Meister

This thread is beating a long dead horse, but perhaps it's still an interesting discussion with some very valuable information. Let me just interject a couple of my observations/concerns:

1. I think there is certainly some strong credibility in the don't change the fluid in a non-maintained transmission, the question is, just what constituted a properly maintained transmission where one wouldn't be at risk, or at least significantly lesser risk, of dislodging sediment? IOW, what's the magic cut-off mileage or age? Regular 10,000 mile changes, 15,000 mile, 20,000 mile, yearly, etc?

I would guess mileage would be more important seeing as it is a sealed system. It is different than say engine oil. I think MM recommends changing "lifetime fill" ATF every 30k if you are going to do it. I probably wouldn't go much further than that if I were planning on changing it. I decided to leave mine alone just after 70k, which I felt was "higher milage" at over double his recommended interval.

2. Given that BMW specifically states lifetime fill on the transmission, one concern I might have is that if I did change the fluid, and something went wrong with the transmission, would they cover it under warranty since they specifically said not to mess with it?

Another good question.

3. Not to add a 3rd component into the mix (engine oil, transmission fluid, and now...) but beginning 2005 model year BMW suddenly went to lifetime fill for the cooling system. Marketing decision? Does it fall under the same circumstances as transmission maintenance, etc?

I would think changing out the coolant doesn't involve any real risk of damage or failure to the cooling system regardless of maintenance/non-maintenance. I would change mine, personally.

[m5james]

...which basically says to either change it every 50k (which I've suggested since day one) or play the odds and leave it be. For those who haven't changed it, then it's on you and it's simply a choice after that. Some have had luck changing the fluid in the 100k range w/ no ill effects and reported better shifting. Some have even changed fluid when they had shifting issues and it solved the problem. Some have also changed the fluid and had failures within days, weeks or months. It seems there is no definate answer, but since I've had no issues changing at 50k, which I've always done, then it's my conclusion that it shouldn't be an issue as long as it's maintained sooner than later, not waiting till issues have already risen.

[FSETH]

Originally Posted by m5james

...which basically says to either change it every 50k (which I've suggested since day one) or play the odds and leave it be. For those who haven't changed it, then it's on you and it's simply a choice after that. Some have had luck changing the fluid in the 100k range w/ no ill effects and reported better shifting. Some have even changed fluid when they had shifting issues and it solved the problem. Some have also changed the fluid and had failures within days, weeks or months. It seems there is no definate answer, but since I've had no issues changing at 50k, which I've always done, then it's my conclusion that it shouldn't be an issue as long as it's maintained sooner than later, not waiting till issues have already risen.

I can agree with your logic. The whole point of my first post in this thread was just to let people know that there ARE risks associated with doing so on an un-maintained automatic trans with higher mileage. It seems important for BMW owners because many people do follow the factory maintenance program, which means there are a ton of BMW owners who either haven't changed their fluid or are planning on doing so for the first time at 100k. Unfortunately, these people fall into the catagory Mr. Miller describes where he has seen many fail after the change. That is all I wanted to point out. I didn't realize this myself until a year or two ago. I was under the impression that new fluid would be 100% beneficial with absolutely NO downsides what so ever. Seems that isn't quite true.

If I buy a low mileage car with an automatic transmission , I will consider changing the fluid out regularly, if nothing else than to make mysellf feel good. My X has 112,000 miles, so I am not going to touch it at this point. Might as well put that money into a rebuilt transmission fund instead.

My next car is going to have a manual anyway, so most of this debate will be inconsequential.

[X5 Meister]

Clearly I type slower than JCL. Damn.

[JCL]

Originally Posted by X5 Meister

Clearly I type slower than JCL. Damn.

Used to be 100-120 wpm. Not sure now. As an aside, it is probably why I don't understand the need for tablet computers (another thread currently running).