Does every 4.4, 4.6 and 4.8

[absentmathis]

Originally Posted by bcredliner

Yes, every 5000 miles. Every mile on new oil means it is not as good as when it poured from the bottle. I say at 5000 miles, it is a small investment to change the oil and filter. I am not saying anyone should do the same thing but there is no way to know if it is obsessive. There is a way to know the oil was not as good coming out as it was going in even after as little as 1000 miles, including synthetic.

I agree it's not about the negligible cost, it's just kinda wasteful. You're running the same interval some manufacturers recommend for non-syntehitic. The manufacturer of your car recommends three times that. Yes - I know they also recommend lifetime tranny fluid, etc.

I'm as picky as anyone about maintenance. But there IS a way to know if your oil is failing or fine. Test a few batches when you change it, that will tell you how fast it's degrading and getting dirty. I've had it tested at 10k and it was totally fine. Even 15k wasn't showing signs of extreme wear. Changing it 'just because' is like changing tires at 50% tread because it could go flat.

[JCL]

Then there are all the studies published by SAE and others that document lower engine wear with used motor oil than new. Makes a case for not changing the oil too frequently.

Some discussion here: used oil better than new? - Bob Is The Oil Guy

[TiAgX5]

I'm a firm believer in the shorter oil change interval too (when 3rd green LED of the SII goes out, so does the oil/filter). It's not just an issue of shear life and metal content of the oil but the combustion by-products and acids that the oil contains.
BMW would certainly consider a total engine rebuild at 200k miles as "acceptable" for an X (or better yet, consider it DEAD and give a $k or 2 as trade in on a new BMW). Some here are running over 300k miles on their engines, I would bet these high mileage X owners are not following the SII for service.

Most manufacturers are pushing the green limits, reducing the carbon footprint of a vehicle during its service life, while also reducing the incurred cost of no charge maintainence programs. It's a balancing act, component life VS dealer service costs, and the manufacturers are posed to lose huge $s by not pushing fluid life limits.

[bpowa]

Originally Posted by A B Able Truck

If you have oil in the intake - it can only be caused by a defective CCV system or excessive crankcase pressure. Oil in the intake should not be considered normal and reduced to as minimal amount as possible. From there you should look for other engine problems if still concuming excessive oil.

The CCVs adjust the vacuum accordingly (if they work as designed) - They are vacuum actuated with no outside influence other then crankcase pressure.

The pressure control valves regulate the crankcase pressure to a low 0>30 mbar.
N62 = 22 mbar vacuum
N62 TU = 25 mbar vacuum
20" (Torr) = 26.66 mbar vacuum

Why else should i check for besides the valves and hose on the valve cover.

It seems more info and diagram pops up for the 3.0 engines when i search.

[TiAgX5]

Originally Posted by JCL

Then there are all the studies published by SAE and others that document lower engine wear with used motor oil than new. Makes a case for not changing the oil too frequently.

Some discussion here: used oil better than new? - Bob Is The Oil Guy

Haven't read thru it all yet, but seeing "in some cases" and "under certain circumstances" verbage in the SAE document makes me wonder.

Why would BMW do a low miles oil change on all high RPM ///M cars? To increase wear on these new, tight tolerance engines?

[A B Able Truck]

Originally Posted by bpowa

Why else should i check for besides the valves and hose on the valve cover.
It seems more info and diagram pops up for the 3.0 engines when i search.

On the V8s and above many "mechanics" scream "your valve stem seals are bad" from any mention of smoke and/or oil consumption. But you guys look like you take it in the logical direction. You fix the obvious first. All of you point to the CCV first and that's good. Then if you still have a problem - maybe valve stem seals, rings, etc. You also need to consider mileage, maintenance practices, enviornment, etc.

[absentmathis]

TiAg, have you ever had your oil tested by Blackstone or similar? I'm running one of those high mileage engines you reference (240k) and for the first half of its life it had dealer service, meaning dealer service intervals. After that oil changes have been 7500-10k, and the thing runs as strong and clean as any.

[TiAgX5]

Originally Posted by absentmathis

TiAg, have you ever had your oil tested by Blackstone or similar? I'm running one of those high mileage engines you reference (240k) and for the first half of its life it had dealer service, meaning dealer service intervals. After that oil changes have been 7500-10k, and the thing runs as strong and clean as any.

Never had an oil test done. I have the same service history on my M62 4.4, dealer oil changes per the SII (service interval indicator) up to 100k, then oil changes when the 3rd LED goes out on the SII with M1 0-40 LL spec for the next 70k miles.

No oil consumption/leaking and runs strong, BMW states a top speed of 143 mph for '03 4.4 with sport pkg (V rated tires added to the sport pkg in '03 allowed them to remove the limiter), I've seen 147 mph GPS indicated on a +2 mile high speed run.

[pezho405]

May have been mentioned but i think its just the 04+ 4.4 and 4.8. Mainly the N62 engine..as well as the n62 745 750 550 545 650 645...

[TiAgX5]

Originally Posted by pezho405

May have been mentioned but i think its just the 04+ 4.4 and 4.8. Mainly the N62 engine..as well as the n62 745 750 550 545 650 645...

+1. Many owners posting blue smoke/high oil consumption threads have post M62 engines ('04 on). These issues were the driving force making me look at '03 4.4/4.6 Xs when I spent over 1 yr looking for a good used X.

Increased labor hrs for most "top end" repairs due to valvetronic system and intermittant shaft levers needing replacement every 20k miles after 100k due to cold start rattle/excessive wear was not something I wanted in a high mileage DD I DIY. The rate I rack up miles (70k in 3.5 yrs), I would need to do them every year.