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

[sunny5280]

Originally Posted by JCL

I believe I can, if my shop did the only maintenance to the vehicles in question, and knew the vehicle history. I have already discounted the cases where changing the fluid was a last ditch effort to avoid transmission repair.

I suspect your shop saw only a small number of BMWs making the sample size too small to be of value.

The shop in question (in my case) was a general repair shop, that did not do transmission work exclusively. We overhauled some tranmissions, and worked with specialist shops that could do it cheaper in other cases. There is a clear correlation with increased failure rates after fluid changes, it wasn't just our shop.

Would you mind posting the supporting data?

That said, clean fluid is a good thing. It just didn't always make transmissions last longer (which was the primary reason that owners wanted to change transmission fluid, to increase the life of their transmissions)

I don't know if it does or not. We replace every other fluid in our vehicles in order to increase service life so I fail to see why the transmission fluid should be any different.

[JCL]

Originally Posted by sunny5280

I suspect your shop saw only a small number of BMWs making the sample size too small to be of value.

A very small number. But that is irrelevant, at least until BMW start to make their own automatic transmissions.

Originally Posted by sunny5280

Would you mind posting the supporting data?

Yes.

Originally Posted by sunny5280

I don't know if it does or not. We replace every other fluid in our vehicles in order to increase service life so I fail to see why the transmission fluid should be any different.

That is getting to the essence of the debate. Think of the risk of an fluid-change induced transmision failure as x. Think of the benefits of clean fluid making the transmission last longer, and that being relevant to the life of the vehicle, as y. It is simply a case of whether the risk of x is greater than the benefit of y. X is greater than 0, it isn't 0. It isn`t an urban legend as you described it above. Y used to be quite large, which is why we used to change transmission fluid every 30,000 miles or so. Y isn't so large today, because we now have factory installed transmission coolers with thermostats, we have lock-up torque converters that keep the fluid temperature down, we have programmed shifts that reduce clutch slip, and we have feedback loops in the actuators so the transmission can compensate for fluid viscosity change over time. Presumably clean fluid could make it last longer, but there are posters here who are over 200,000 miles on the original transmission fluid. Many transmission will last longer than the chassis, simply because it will become too expensive to do software updates. These are not cars that are going to be cheap to own as they age, and that is going to greatly reduce the number of them on the road. At the same time, there are lots of early hour transmission failures (lots is relative, let's just say more than we would like to see) and they do not appear to be related to oil quality, but rather random failures of software, sensors, etc. Not things that would fail less frequently if the oil was cleaner. What happens is that because of those early hour failures, owners consider changing the fluid to improve their odds. That is faulty logic.

It is simply a judgement call that each owner has to make. There is no right and wrong answer, there are just risks. I think it is worth pointing out that not changing the fluid is not some nonsense dreamed up by a marketing organization at BMW, there is a technical reason and in many cases it makes sense. If owners are going to change the fluid, then I think that they have to change the filter at the same time, they probably should change it two or three times in short order to get the bulk of the old oil out (since there is no torque converter drain), they should use factory spec oil and not try the roulette game of various aftermarket oils that may or may not work, and they should refill it according to the BMW procedure that involves taking fluid temperature readings during setting the level.

[BMWvoid]

Hello ArNarX5.

I know oil flushing is not a popular remedy on this website. In two of my previous cars I used BG products for preventive maintenance.

Here are a couple of links for your review:

MotorWeek: Auto Basics: Goss' Garage

BG Products, Inc.

I see you are in Burbank. I have my X5 serviced at Center BMW. They do not have the BG service. Casa Motors in Sherman Oaks does. I had the BG oil flush done on two of my SAABs at 30k as discussed in the MotorWeek article. I did this based on my dad's recommendation, not MotorWeek. I just saw this MotorWeek episode in 2009.

I have no direct expertise in car maintenance. My dad was the mechanic, a retiree from LA City. He retired 20 years ago, so I know he was trained old-school. Funny thing, he worked on all his cars, up until his death last year at 84. The only work he would not do was related to air conditioning. Sorry for the digression.

[sunny5280]

Originally Posted by JCL

A very small number. But that is irrelevant, at least until BMW start to make their own automatic transmissions.

Given you've only seen a small number I will restate that your sample size is too small to be of relevence.

That is getting to the essence of the debate. Think of the risk of an fluid-change induced transmision failure as x. Think of the benefits of clean fluid making the transmission last longer, and that being relevant to the life of the vehicle, as y. It is simply a case of whether the risk of x is greater than the benefit of y. X is greater than 0, it isn't 0. It isn`t an urban legend as you described it above. Y used to be quite large, which is why we used to change transmission fluid every 30,000 miles or so. Y isn't so large today, because we now have factory installed transmission coolers with thermostats, we have lock-up torque converters that keep the fluid temperature down, we have programmed shifts that reduce clutch slip, and we have feedback loops in the actuators so the transmission can compensate for fluid viscosity change over time. Presumably clean fluid could make it last longer, but there are posters here who are over 200,000 miles on the original transmission fluid. Many transmission will last longer than the chassis, simply because it will become too expensive to do software updates. These are not cars that are going to be cheap to own as they age, and that is going to greatly reduce the number of them on the road. At the same time, there are lots of early hour transmission failures (lots is relative, let's just say more than we would like to see) and they do not appear to be related to oil quality, but rather random failures of software, sensors, etc. Not things that would fail less frequently if the oil was cleaner. What happens is that because of those early hour failures, owners consider changing the fluid to improve their odds. That is faulty logic.

I don't see replacing fluids as faulty logic. We do it for engine oil so why shouldn't we do it for transmissions?

I do agree that fluid life has increased considerably over the years. That doesn't make it lifetime fluid.

As for X I have seen no data, and you refuse to provide your own, that supports it is significant. Is there a risk? Most certainly. And by your own admission that risk is slight. Is there a correlation? I haven't seen any. All I've seen is an urban legend with no supporting facts.

Does your hypothesis seem reasonable? I think it does...in a handful of situations.

It is simply a judgement call that each owner has to make. There is no right and wrong answer, there are just risks. I think it is worth pointing out that not changing the fluid is not some nonsense dreamed up by a marketing organization at BMW, there is a technical reason and in many cases it makes sense. If owners are going to change the fluid, then I think that they have to change the filter at the same time, they probably should change it two or three times in short order to get the bulk of the old oil out (since there is no torque converter drain), they should use factory spec oil and not try the roulette game of various aftermarket oils that may or may not work, and they should refill it according to the BMW procedure that involves taking fluid temperature readings during setting the level.

Aftermarket and incorrect fluids are irrelevant to this discussion. If they result in transmission failures we're no longer discussing if changing the fluids is risky but rather using the correct fluids results in failure. My assumption in this discussion is the correct fluids are used and the fluid is change properly. Under those circumstances I (as well as you) see little risk in changing the fluid and potential upside. Y outweighs X easily. And until I see data showing otherwise I'll continue to conclude transmission failure from properly changing the fluid is nothing more than an urban legend.

[m5james]

Originally Posted by Naz24

as for your poll, my service advisor told me that BMW recently redefined lifetime as 100k, so according to BMW you should change the trans oil. But on the other hand, there are certain particles in there that you might not want to lose

And since BMW can't take it's head out of it's ass and stick w/ one answer, I'm still going to keep doing them at 50k for my own sake.

[JCL]

Originally Posted by sunny5280

I don't see replacing fluids as faulty logic. We do it for engine oil so why shouldn't we do it for transmissions?

Because, to use the same logic as I provided you for the transmission, in the case of the engine oil x approaches zero, and y is significant. Engine oil is designed to be drained, a drain is provided, draining doesn't cause other problems, etc. Not changing engine oil impacts engine life. The fluid doesn't wear out (oil is slippery for its entire lifetime, as I am sure you know) but it gets contaminated by byproducts of combustion, and the additive package gets depleted. Comparing engine oil to transmission fluid is nonsensical. It would be much better to compare transmission fluid to shock absorber fluid, they are both hydraulic oils in sealed systems. You could change your shock oil I suppose; many years ago we used to rebuild shocks, particularly lever type shocks. Now they have lifetime fluid in them. Not your lifetime, the shock absorber's lifetime. Maybe that is a plot to get us to buy more shock absorbers.

[JCL]

Originally Posted by sunny5280

My assumption in this discussion is the correct fluids are used and the fluid is change properly. Under those circumstances I (as well as you) see little risk in changing the fluid and potential upside. Y outweighs X easily. And until I see data showing otherwise I'll continue to conclude transmission failure from properly changing the fluid is nothing more than an urban legend.

How are you going to properly change a fluid that isn't designed to be changed? How are you going to drain it all?

For you, Y outweighs X. That is reasonable. For me, it doesn't, and I generally know how to work on the vehicle, and how to obtain the correct fluid. I provided the X and Y framework to try and move this into a more reasoned discussion. You see X as very small, I see it a little larger. You see Y as large, I see it as practically zero.

You keep calling X an urban legend, but that is insulting. My decision is based on over 25 years of relevant work experience, shop experience, oil lab experience, my mechanical engineering training (including tribology courses), and years of service management. The phrase urban legend puts all that in the same category as the yeti. You certainly don't have to agree with everyone, but you should at least respect other's opinions.

[m5james]

Jesus christ, this is the most beatin to death topic. At the end of the day, its a fluid...NO fluid is lifetime, so why in the hell wouldnt anyone want to replace it. Even BMW (because they are the holygrail ya know) has even revised their own suggestion of lifetime because they realized the err in their ways. Its now a serviceable item on newer cars, so why wouldn't we retro that same new practice to older cars...which are WELL known to have transmission issues. Sure, no one can prove beyond a reasonable doubt one way or another if changing vs not changing the fluid is a factor is transmission failure, so I revert back to my original statement - absolutely NO fluid is lifetime. Comparing a shock absorber and its 1 moving part to a transmission and its countless moving parts...now that is nonsensical. People...either change your fluid or don't, do whatever makes you happy. If someone wants to follow the (imho) blind advice that BMW has since stopped practicing, that's up to you. I know what I'm going to do, and its far less expensive to do every 50k vs a $4k transmission replacement. There will be just any arguements for as there are to not change it, so to each their own. How the OP turned the title of this thread and combined a transmission poll is beyond me...good job man, see the pot you've stirred

[m5james]

Originally Posted by ArNarX5

So I changed the oil for the very first time on the 03 4.4 I just bought two weeks ago and to my surprise.... WOW: wow: talk about sludge everywhere in the in the engine and filter housing! I was disgusted.

How could someone be so careless to leave their oil in the car so long that it turns into sludge!?! There was rock like black crystals in an oil filter that said it was made in India.

Needless to say, I cleaned whatever I could in the oil filter housing and drained ALL of the nasty burnt oil from the car and replaced with OEM Oil Filter and Almost 9 Qts of Mobile 1 5w/30.

The car has 100k on it and the engine runs fine as if you could not tell it has that entire gunk built up inside of it.

My Question....

What can I do to safely remove all the build up from inside the engine components? I am planning on dumping this oil in about 2,000 miles and it's a waste since it's Mobile 1 and cost almost $70. Has anyone ever had a similar situation? If so, how did you deal with it?

Any thoughts would be appreciated!

You can either use an off-the-shelf internal engine cleaner from your local autoparts store, WalMart, etc or you can even use ATF...Google for the ratio as I'm not sure. Just be prepared for all the sludge to dislodge itself and possibly expose leaks that were plugged by the sludge before- valve covers, oil pan, etc.

[JCL]

Originally Posted by m5james

this is the most beatin to death topic.

Sure it is, but that is why it is called a Discussion Board, not a reference library. Sunny is new here, and hasn't participated in the discussion previously, so he gets to discuss it. We all agree there is no one single answer, so no need for the angst.