[ward]

Originally Posted by epiphone3

this 528 was probably driven on the high way alot or regularily had long drives.

Bottom line is not that something else happened to the engine in the first post. It is actually that no one knows for sure what caused the sludge in the first place... however, what we do know is if you change your oil every 7,500 miles rather than the BMW recommended 15,000 miles, you will have an engine that looks brand new inside at 100K+ miles.

And by the way, I doubt that the crank case vent was blocked on the car in the original post as probably would have caused a gasket or seal to blow or other problems before the sludge... if the crank case breather got blocked, it was probably by a chunk of sludge.

so we have a case where a car that had it's oil changed twice as often as factory required stayed clean...

what we don't have evidence is that a properly maintained car with factory intervals will sludge up.

bottom line is none of this evidence is strong enough to make a case for either side, we have 2 pictures of engines.. not hundreds or thousands

it's probably possible for a car with synth oil changed every 3k to sludge up if other malfunctions/conditions were right

it's probably also possible for a car to run 20K (5k longer than the interval) and never sludge up at all.

[Div4our]

Originally Posted by ward

so we have a case where a car that had it's oil changed twice as often as factory required stayed clean...

what we don't have evidence is that a properly maintained car with factory intervals will sludge up.

bottom line is none of this evidence is strong enough to make a case for either side, we have 2 pictures of engines.. not hundreds or thousands

it's probably possible for a car with synth oil changed every 3k to sludge up if other malfunctions/conditions were right

it's probably also possible for a car to run 20K (5k longer than the interval) and never sludge up at all.

Who ya gonna call?


MYTHBUSTERS!

[ward]

Originally Posted by division4our

Who ya gonna call?


MYTHBUSTERS!

they can start working on it now, and the story will be ready in 5 years

[grkm3]

Originally Posted by Mr Crutch 325i

Interval is the same in Europe and they DON'T get free oil changes, so unless BMW made that decision based ENTIRELY on the US Market (talk about being conceited) that is NOT the reason.

BMW techs over here will tell you that you are babying the engine if you keep bringing it in for oil changes.

Thats funny because when I had my new e46 they would change it when I brought it in no questions asked,because they were blowing up engines left and right and yea call me a baby but at one point I was afraid to take my car out and drive it with the fear of punching a hole in my block.Even my SA said that 15k is rediculus and they ALL agreed.BMW came out with a special oil after for our cars,castrol 10w60.

Ask some of your buds if they go 15k miles on the same oil in there M5s and M3s over there and tell them there babies lol.BMW only cares about us for 50kmiles and then were on are own,sludge and all the engine problems would start right after that point.

[tctic]

Originally Posted by epiphone3

wrong. Oil life in the BMW computer is based almost entirely off of measured fuel consumption.

My claim that the E90's have oil quality sensor is based off a post made by E90Fleet some months ago. Though this is my only backup, his info is generally accurate. But whether the N5x engines really have oil quality checks, I have yet to see further proofs.

http://www.e90post.com/forums/showpo...41&postcount=8

[epiphone3]

Originally Posted by ward

so we have a case where a car that had it's oil changed twice as often as factory required stayed clean...

what we don't have evidence is that a properly maintained car with factory intervals will sludge up.

um, we actually have several people also posting that their engines have the same look after x amount of miles and more frequent oil changes.

What we really don't have is any one showing up with an engine that has 100K+ miles with oil changes every 15,000 - 20,000 miles saying that their engine is as clean as a whistle... except of course for your single example that could just be the rare person that drives on the highway alot or has a long commute without too much stop and go traffic.

[epiphone3]

Originally Posted by tctic

My claim that the E90's have oil quality sensor is based off a post made by E90Fleet some months ago. Though this is my only backup, his info is generally accurate. But whether the N5x engines really have oil quality checks, I have yet to see further proofs.

http://www.e90post.com/forums/showpo...41&postcount=8

I believe that E90Fleet later recinded on his claim of the sensors measuring oil quality, but I can't remember for sure.

[tctic]

Originally Posted by e.n335

you know now what can happen. I have no idea why ppl resist to do really good things to their engines when it's that easy and that cheap. You are informed now and it's your engine. I completely disagree to the approach "BMW said this, so it has to be good". When you DIY we talk about $600 - $800 in a 3-4 year period. It's worth the money and the condition of the engine after that period.

I agree that there is absolutely no harm in anyways for a more frequent oil change interval. I just believe if you follow the recommended service, your engine will serve the car well for the lifetime of it.

As opposed to you, I do believe BMW is making the correct recommendation on oil change intervals as it doesn't seem to benefit BMW in anyways (in the big picture) by recommending such a 'long' oil change interval. If the current recommended oil change interval is not adequate for sufficient engine protection, then I serious think BMW would never recommend it as it will seriously affect its reputation in the long run due to premature reliability issues with the engine.

[tctic]

Here's the post of E90 quoting BMW literature that it does have a oil quality sensors that feeds data to the ECM of the engine for oil change interval calcuations.

http://www.e90post.com/forums/showpo...9&postcount=16

[The Cleaner]

I think this post is right on target, plenty-o-assumptions going on to imply the 15k oil change interval has anything to do with this mess.

I had a 528 come in with about 6k on the filter and oil but the owner wanted it changed anyway, I opened the filter housing and the filter paper had completely been destroyed, the paper was in little 1mm chunks and distributed all over the engine. Much of what I found under the V/C was similar to the photos in this post. It was so bad the oil was not draining out of the housing.

Originally Posted by ward

this is just sensationalism for the sake of sensationalism

the picture is dramatic, but does it mean anything....


for all we know the owner abused the car and used dino oil instead of synthetic as required.

running dino for 15000 has disctinctly different effects than running the proper synthetic

if you had evidence that this car was maintained to factory specs using factory correct oils then we may have an issue to be concerned about.

for all anyone knows he may have put dino oil in 50,000 miles ago and left it

[epiphone3]

Originally Posted by tctic

Here's the post of E90 quoting BMW literature that it does have a oil quality sensors that feeds data to the ECM of the engine for oil change interval calcuations.

http://www.e90post.com/forums/showpo...9&postcount=16

then when I do a DIY oil change, why doesn't the sensor detect the fresh, new oil and add thousands of miles to the time remaining for oil service?

[tctic]

Originally Posted by The Cleaner

I think this post is right on target, plenty-o-assumptions going on to imply the 15k oil change interval has anything to do with this mess.

I had a 528 come in with about 6k on the filter and oil but the owner wanted it changed anyway, I opened the filter housing and the filter paper had completely been destroyed, the paper was in little 1mm chunks and distributed all over the engine. Much of what I found under the V/C was similar to the photos in this post. It was so bad the oil was not draining out of the housing.

I believe the new oil filters are re-engineered to last as long as the recommended oil change intervals now. (Again, recalling from a post by E90Fleet some months ago as my source of info.)

[tctic]

Originally Posted by epiphone3

then when I do a DIY oil change, why doesn't the sensor detect the fresh, new oil and add thousands of miles to the time remaining for oil service?

Not 100% sure but notice that your count down only counts down and never counts up? It just counts down slower if the car thinks the oil is still in good condition. Also, the count down also takes fuel consumption, distance travelled, speed, etc in to the calculation formula. It only takes the sensor's info as part of its raw data in achieving the 'next recommended oil change time'.

[epiphone3]

Originally Posted by tctic

Not 100% sure but notice that your count down only counts down and never counts up? It just counts down slower if the car thinks the oil is still in good condition. Also, the count down also takes fuel consumption, distance travelled, speed, etc in to the calculation formula. It only takes the sensor's info as part of its raw data in achieving the 'next recommended oil change time'.

I do DIY oil changes. No matter of the oil is brand new or has 8,000 km on it, the counter still goes down by 1000 km every 1000 km I drive.

New oil doesn't seem to affect the service interval in any way... hence I highly doubt the oil quality sensing has any weight in the service interal calculation if it is occuring at all.

[NaTuReB0Y]

I do my oil change every 5,000 miles and the countdown is not effected by it.....

it still counts down as slow as ever.............

[A418t81]

Why add unnecessary complexity with "oil quality sensors" when monitoring the fuel economy, which obviously reflects driving habits and engine load, is already there?

[F32Fleet]

My $.02. BMW began offering extended oil changes beginning with the E46. There are thousands of E46's on the road with over 100k/miles and you don't hear about these engines developing sludge.

FACT: The rest of the car will die before the engine does. Unless you're tracking your car, don't act like a nanny and fret over oil changes.

[e30klassic]

What if some lazy azz worker that just top the oil off 7 reset the service light?!?
Local news busted a few places for doing it down here i the BayArea.

How would we know?! Especially with our E9X......No stick.

[turbotko]

Originally Posted by epiphone3

And by the way, I doubt that the crank case vent was blocked on the car in the original post as probably would have caused a gasket or seal to blow or other problems before the sludge... if the crank case breather got blocked, it was probably by a chunk of sludge.

It was actually mostly highway driven which no doubt helped the situation out, but it had been serviced on the dot per counter in the cluster.

And by the way, there are many many more things that can disable a crankcase ventilation system besides being blocked. Many of them won't have any immediate symptoms until it develops enough of a vacuum leak to turn the MIL on, thus the car can go 10-30K miles with no crankcase ventilation system before it gets repaired.

It will never hurt anything to change the oil in between the intervals, alot of people like doing it. Just make sure you're using BMW filters (alot of the aftermarket ones are known for coming apart in the housing)and good oil. Me personally, I am leasing my 335i, and it will only get it's oil changed on the recommended service intervals.

[Jaws]

Originally Posted by epiphone3

I do DIY oil changes. No matter of the oil is brand new or has 8,000 km on it, the counter still goes down by 1000 km every 1000 km I drive.

New oil doesn't seem to affect the service interval in any way... hence I highly doubt the oil quality sensing has any weight in the service interal calculation if it is occuring at all.

I agree. Just got my "free" oil change done at the dealer last week (still had 14k km remaining, but I got in under the 1 year rule), and they forgot to reset the computer. Now it says 13k km. Another free oil change in 13k km As per the bulletin from BWM, the oil change algorithm is baseed on mileage only.

[epiphone3]

Originally Posted by turbotko

It was actually mostly highway driven which no doubt helped the situation out, but it had been serviced on the dot per counter in the cluster.

And by the way, there are many many more things that can disable a crankcase ventilation system besides being blocked. Many of them won't have any immediate symptoms until it develops enough of a vacuum leak to turn the MIL on, thus the car can go 10-30K miles with no crankcase ventilation system before it gets repaired.

It will never hurt anything to change the oil in between the intervals, alot of people like doing it. Just make sure you're using BMW filters (alot of the aftermarket ones are known for coming apart in the housing)and good oil. Me personally, I am leasing my 335i, and it will only get it's oil changed on the recommended service intervals.

not surprising that the 528 you serviced with lots of highway miles didn't make sludge on regular service intervals... highway driving is so much better for oil than city driving.

One thing... when you get your 335i serviced after 15K-20K miles write back here. I guarantee that the words "drives like a champ again," "drives like a BMW again," or "drives like new again" will come out of your mouth... that and "seems much smoother now!" I keep my car in that shape all of the time by changing every 8,000km.

[tctic]

Originally Posted by Jaws

I agree. Just got my "free" oil change done at the dealer last week (still had 14k km remaining, but I got in under the 1 year rule), and they forgot to reset the computer. Now it says 13k km. Another free oil change in 13k km As per the bulletin from BWM, the oil change algorithm is baseed on mileage only.

They do not reset anything with the 'one year rule'. Unless you are really really close to the end of the countdown according to my dealer, they will just change the oil and filter.