Oil Quality & Quantity (35i)

[tiborakos]

Hello,

am about to perform an oil change in my sdrive35i, and wonder what specs are out there.

I think BMW uses Castrol 5W30 as a preference, but what is the quantity required for the N54 engine? Is the 6.5L or 8.5L that is needed?

What other oil (brand - specs ) will you recommend?

thanks

PS. it is amazing how much pricing vary @ various bmw service places, so far is from 150 eur to 200 eur...
PS2. i got the quantity as 6.5L from the following thread http://e89.zpost.com/forums/showthread.php?p=6912580

[m6pwr]

In U.S. models, the N54 takes 7 quarts = 6.6 liters. A good alternative to the factory oil is Castrol Syntec 0w-30 European Formula. It is a pretty stout oil, PAO base stock with a cut of ester, nearly a 40 weight with very little shearback under high heat and revs, and a high flashpoint, all meaning it works pretty good in an oil-cooking turbo charged motor. It is made in Germany so many folks here simply refer to it as "German Castrol" to differentiate it from the other types of Syntec. In the U.S. it is one of the few oils specifically listed by BMW of North America as a suitable alternative to the BMW High Po oil. There are many others, but whatever you use be sure it meets BMW's Long Life LL01 spec and is ACEA rated A3B3. Another good one might be Motul BMW LL-01 5w-30 or Motul 8100-Max 5w-30. Both meet BMW's specs and are ester based, high quality oils ($$$).

[m6pwr]

As an afterthought: I expect that the 150-200 euro figure you quoted is for an oil and filter change in a N54 Z4. I know it will be expensive but I would highly recommend more frequent oil changes than what BMW recommends; do something on the order of every 5000-7500 miles. The N54 twin turbo direct injection engine places a lot of stress on its lubricant with very high temps and possibility of fuel dilution which can pretty much destroy oil.

[Alext]

Mobil 1 0W-40 is the oil I will be using and have used on the N54 engine. It is BMW LL01 rated so you're good to go.

[cdeslandes]

From BMW literature:

BMW Long-life rating LL-01
Approved Synthetic Oils for the US Market

Castrol Syntec European Formula SAE 0W-30
Mobil 1 SAE 0W-40
Pennzoil Platinum European Formula Ultra SAE 5W-30
Valvoline SynPower SAE 5W-30

[teagueAMX]

Originally Posted by m6pwr

The N54 twin turbo direct injection engine places a lot of stress on its lubricant with very high temps and possibility of fuel dilution which can pretty much destroy oil.

The high temps I understand, particularly in hot areas with stop and go traffic, but how do you account for the possibility of fuel dilution? With direct injection, unless you have a malfunction, I don't buy that at all. Please enlighten me.

[m6pwr]

Well...I did say "possibility" of fuel dilution. Surf some on BITOG and you'll find that turbocharged di engines have the reputation of diluting the oil with fuel. One explanation/theory I've heard is that with atomized fuel immediately present in the combustion chamber, the very high mean effective pressures in the turbo-charged cylinder can push minute amounts of fuel past the rings. I don't know if it is technically true or not and I'm not prepared to argue the point. I have read that if fuel dilution gets above 3% you've got problems (mainly I think with viscosity reduction but also adverse effects on additive performance). I just did a used oil analysis (UOA) at only 1500 mi on my N54 on the factory fill and there is some very minor fuel dilution noted (less than 0.5%), and the averages (as noted by the UOA lab) for these engines can get up to around 2%. I've also read that fuel dilution is fairly common in diesel engines - - don't know why exactly - - but that for some reason diesel oils can tolerate as much as 6 or 7% dilution (probably the nature of the fuel).

If you're not familiar with BITOG (Bob Is The Oil Guy), it is a forum of about 35k members obsessed with lubricants. Most are rank amateurs (like myself) but there are some very knowledgeable people who are professionals of one stripe or another who work in the lubricants industry. I'll post your question/challenge and see what comes back. In the meantime, here is the BITOG forum on euro cars:
http://www.bobistheoilguy.com/forums...oard=48&page=1 There are a couple of threads going on now on the N54/N55.

I'm running German Castrol in my motor now and will do a UOA after around 2500-3000 mi to see what I get. I'll post the results. If everything looks ok, I'll run longer oil change intervals. The z4 is my first turbocharged di engine.

[teagueAMX]

Thanks for your well articulated and honest response.

I totally agree with you if significant amounts of fuel is pushing past the rings based on high cylinder pressures that spells trouble. On the other side, I think you'd be hard pressed to find a more efficient fuel metering and atomization system than direct injection, regardless of auto manufacturer - BMW, Audi, Porsche, etc. Given that turbos have been use for many years, and with far less efficient injection systems, I'd be curious if PCA or others has discussed it. I'll check that out.

First I've seen that acronym BITOG but somebody else mentioned Bob the other day. I'll drop by there but I would appreciate feedback from the group as you suggested.

Cheers.

[teagueAMX]

m6pwr, again thanks for the tip.

I registered with the BITOG but they have to approve my account. In the mean time I did snoop around and found the posts you mentioned. Even saw at least one by you.

My initial reaction is there's a lot theory about motor oil. Kind'a reminds me of a friend who likes to have very esoteric discussions about wine: after a while I say - Hey! can we just drink it! And, as you mentioned, the issue of fuel diluting the oil was there in abundance. Of note, however, FrenchTex had some real world analysis pertaining to BMW turbo charged engines that I felt was very relevant:

FrenchTex @ BITOG:

Hey Guys,

This is only my second post here, but since I own a 535i, I did quite a bit of research on oil and OCI and think I may be able to offer "some" insight:
- PN 07510002545 is in fact an old PN, and it was superceded by PN 07510017866 which is indeed the BMW synthetic 5W30. BMW, at least in the US, only offers this oil for all gasoline engines
- It seems in countries outside the US, BMW specifies an LL-04 oil for the X35i (N54 engine) but we cannot use it in the US due to differences in fuel quality and a richer fuel injection. I found no data as to whether this oil mitigates fuel dilution issues or high temperature issues
- Forums (not only BITOG) do show some data of lousy UOA after 1000 mi oil changes, but at the same time, I have seen several UOA reports of owners of 335i with OCI of 4000, 6000 and 7000 whose data looked pretty good. I have even found 1 report where a guy had done a 14kmi OCI and his oil was not great but not as terrible as one might think (the oil had thickened to a 15W40 equivalent and only had 2% TBN)

Like other owners I concluded the following:
- BMW's recommendation of 15kmi OCI is more than optimistic, so for anyone keeping the car long term, a safe bet is to do a shorter OCI
- That shorter OCI could be as short as 1 to 2kmi for someone driving in "severe" conditions (cold start, numerous short trips, high power acceleration, tracking) and as long as the full OCI (for someone driving a very long commute for example)
- There is no recent data that I have seen lately justifying the concern over fuel dilution. There was a lot of talk about 2007 and early 2008 models, but since then, every UOA I have pulled showed no sign of massive fuel dilution. I am in fact wonderring if the fuel map has been altered by BMW in recent versions of the DME
- Everyone has seen that these engines run hot (from 240 to 280F in every day applications), however, similarly to the fuel dilution, all the recent UOA I have seen showed nothing worse than 1 grade worse of shearing or 2 grades of thickening for the cold viscosity measurement

As far as I am concerned, I did an oil change at 2400mi (break-in), will do one at 6500mi with a UOA, and then I will get a free one at 1 year and about 10,500mi. I will do a second UOA then and determine how frequently I need to change oil. I have also purchased some Motul X-Max 5W40 for summer application.

http://www.bobistheoilguy.com/forums...18#Post1959818

Some of those guys really know what they're talking about, but frankly, it's no reflection on anyone here or there, but I can't completely buy into the concept that significant amounts of fuel are getting past the piston rings. I'm not closed minded about it but would need read info based on at least two or three complete engine tear downs, and/or significant report of premature engine failures.

On the other hand in fairness to their forum, I haven't had a chance to really research what they have to say, but once my membership is approved I'll dig in more. At this point I think the n54 twin turbo heat factor is a more significant factor. For that reason alone it may be a good reason to slightly shorten the time span between oil change. Your suggestion about the oil analysis is a good idea as well.

Cheers.

[juhap]

Originally Posted by teagueAMX

My initial reaction is there's a lot theory about motor oil. Kind'a reminds me of a friend who likes to have very esoteric discussions about wine: after a while I say - Hey! can we just drink it!

+1

Personally I just rather enjoy the car than lie awake at night worrying about fuel dilution or if I've remembered to follow the correct e-brake activation procedure. This kind of car is supposed to relieve stress, not increase it.

[m6pwr]

Didn't mean to go off the deep end on oil. I agree basically with what juhap said. I try to control the things that I can and not worry about the things I can't. So...like juhap says, just BOOT IT! But, I do like to keep track of what's happening in the deep, dark recesses of my N54, so I do regular used oil analysis -- and sleep well at night.

The answer to my post on BITOG, for those interested, is here - http://www.bobistheoilguy.com/forums...56#Post1966656

[Memphis1]

Originally Posted by m6pwr

Didn't mean to go off the deep end on oil. I agree basically with what juhap said. I try to control the things that I can and not worry about the things I can't. So...like juhap says, just BOOT IT! But, I do like to keep track of what's happening in the deep, dark recesses of my N54, so I do regular used oil analysis -- and sleep well at night.

That means you do worry...

[m6pwr]

I won't quibble. Actually, I prefer to think of it as morbid curiosity.

[teagueAMX]

Originally Posted by m6pwr

Didn't mean to go off the deep end on oil. I agree basically with what juhap said. I try to control the things that I can and not worry about the things I can't. So...like juhap says, just BOOT IT! But, I do like to keep track of what's happening in the deep, dark recesses of my N54, so I do regular used oil analysis -- and sleep well at night.

The answer to my post on BITOG, for those interested, is here - http://www.bobistheoilguy.com/forums...56#Post1966656

You're alright. Having your oil analyzed is not a bad thing and you don't sound like you have motor oil OCD. I previously read the responses to your question and appreciate it - thanks.

[tiborakos]

Think i have to go back to university and study, but what is actually the difference between 0w-30 5w-30 (Motul BMW LL-01 or Motul 8100-Max or Castrol, or whatever)
Similar specs, different onomatology? which one is preferable?
Z4 is now @ the service spot for oil change, first quote i got is something like 18EUR/lt (ouch!) + filter + 15eur WORK(!!!)
will have analysis tomorrow...welcome to BMW world, hahaha

[m6pwr]

Tiborakis:

If you're so inclined, you can learn about the different terms used to describe oil here:
http://www.carbibles.com/engineoil_bible.html

You can find what BMW thinks are oils as good as theirs by checking BMW AG's Greek site here: http://www.bmw.gr/master_rebrush/en/...andwidth=vhigh
Use the search function to find "approved synthetic oils".

I'm most familiar with Castrol Syntec 0w-30 European Formula. I have used it in several different BMW's. I think its a top notch oil. I don't know for sure what this oil is called in Europe/Greece (it may be called Castrol Edge 0w-30). Check the Castrol Greek site here: http://www.castrol.com/castrol/castr...ategoryId=3110
If you can get ahold of a bottle, it will say on the back that it meets BMW LL-01 stds, is ACEA (euro auto mfrs) rated A3/B3 (high temp/high rpm), and if you look carefully, you'll see Made in Germany. That's what we call German Castrol in the U.S. You can learn a little bit more about it here: http://matrixsyntheticoils.com/store...n_castrol.html
That's a good site to also read descriptions of other brands of oil (i.e. Motul). By the way, the terms 0w,5w, etc. refer to how well the oil flows, at start-up, at low temps. A 0w-xx oil flows better than a 5w-xx oil, which flows a lot better than a 20w-xx oil, and so on. If, during the winter months, you start your z4 in sub-zero temps (like minus 40 F) then get the 0w-30, otherwise 5w-30 is fine.

The BMW twin turbo engine, code named N54, is a fantastic piece of machinery, equal in many ways to the best BMW M engines. But it does place high demands on its lubricating oil. The little turbos, which are both cooled and lubricated by the oil, can reach speeds of 200,000 rpm and operate in an environment that reaches 1050 C or 1900 F. The performance of any oil is going to deteriorate the longer you run it in the engine, and it may deteriorate a lot faster in the N54. That's why I'd recommend changing the oil more frequently than dictated by the BMW computer. Around 5000-7500 miles would be a start.

Hope this helps.

[teagueAMX]

Originally Posted by m6pwr

The BMW twin turbo engine, code named N54, is a fantastic piece of machinery, equal in many ways to the best BMW M engines. But it does place high demands on its lubricating oil. The little turbos, which are both cooled and lubricated by the oil, can reach speeds of 200,000 rpm and operate in an environment that reaches 1050 C or 1900 F. The performance of any oil is going to deteriorate the longer you run it in the engine, and it may deteriorate a lot faster in the N54. That's why I'd recommend changing the oil more frequently than dictated by the BMW computer. Around 5000-7500 miles would be a start.

Hope this helps.

Think maybe you should qualify this a little more closely so people know what you're thinking.

• You're suggesting splitting in half BMW's scheduled maintenance program. What about various climate zones, and different driving styles?
• Also, there's plenty of BMW's for sale that are a few years old and have only a few thousand miles. What about their schedules?
• Here's another consideration: My sense is that BMW honestly believes their schedule is adequate for most people's situations. Even with the typical 4 year 50,000 mile cycle, I think BMW has more $'s to lose than the cost of a free oil change as compared to major engine repair at BMW expense.

[m6pwr]

Originally Posted by teagueAMX

Think maybe you should qualify this a little more closely so people know what you're thinking.

• You're suggesting splitting in half BMW's scheduled maintenance program. What about various climate zones, and different driving styles?
• Also, there's plenty of BMW's for sale that are a few years old and have only a few thousand miles. What about their schedules?
• Here's another consideration: My sense is that BMW honestly believes their schedule is adequate for most people's situations. Even with the typical 4 year 50,000 mile cycle, I think BMW has more $'s to lose than the cost of a free oil change as compared to major engine repair at BMW expense.

These are all good and pertinent questions. I can't answer them directly. The answers, particularly re the first question, lie in doing Used Oil Analyses (UOA's). Blackstone Labs is one of the more popular ones used by bimwads for UOA's. Their web site is pretty thorough and explains the purpose and benefits of UOA's, what the reports look like, etc. http://www.blackstone-labs.com/

Send an email re your last question to Mike Miller who writes a tech column for BIMMER magazine and the ROUNDEL (BMW CCA). He will probably give you an ear full. bimmertqa@aol.com. He responds very promptly and your question might even wind up in BIMMER. I have no idea of what the BMW oil will look like in the N54 at 2k, 5k, 7.5k or 15k. The N54 is terra incognita for me. That's why I would do UOA's. When I changed oil in my N54 at only 1500 mi, to replace it with GC, it looked pretty good except for one property, viscosity. It looked to me like the oil had sheared back rather badly, to almost a 20 wt. It shouldn't do that (shear back is most often the result of high temps and high revs). Viscosity at 100 C (210 F) was 9.5 (the range for 30 wt at that temp is 9.3 - 12.4). To really tell if the oil is shearing back, you have to know what the vis is when the oil comes out of the bottle. You can tell that from Product Description Sheets from the mfr (there aren't any for BMW HP oil), or you do a Virgin Oil Analysis (VOA) on oil straight from the bottle. I did a VOA for the BMW oil a couple of years ago, but I can't find it. But I remember it was formulated at the upper end of the range - - around 11, almost a 40 wt. The VOA for GC at 210 F is 11.9. Every UOA I'v ever done on that oil (on a normally aspirated 330i ZHP) after about 4k mi was 11.9 - - right on the money. The 1.5 mi UOA on my Z54 is at http://www.bobistheoilguy.com/forums...16#Post1964516
There's another one (N55) at http://www.bobistheoilguy.com/forums...89#Post1964489

All of this is probably much too anal or esoteric for most folks. The engines aren't going to blow up or come to a screeching halt before 4yrs/50k mi. It is what they are going to perform like at 75k or more (maybe flickering oil pressure lights in heavy traffic, or tubos that suddenly go south, reduced performance - - how would a second or third owner know?). I don't know - - I've never kept a new BMW for more than 2 or 3 yrs or past 50 k miles.

[teagueAMX]

Thanks

[zenman]

Thanks to the many who invest in good discussion points to provide some quantitative/objective awareness. Forgive my qualitative offering...
I have long been an advocate of frequent oil changes but recognize that technology (synthetic oils) challenge conventional paradigms. Saying that, beware the recommended ~11,000 mile service interval. Just changed the oil/filter on the Z4 (N54) at 9000miles and noted very dirty somewhat thickened oil (not completely sheared) - the engine noise has substantially lessened at ~3000RPM and the idle is smoother as a well. The car has some spirited driving experiences but is mostly a 50 mile/day highway transporter. Not intending to send off for UOA to help quantify but agree with and support heeding M6PWR's point that driving style and ultimate intentions for keeping vehicle need to be considered. My experience although not quantitative, would suggest that the engine would benefit from shorter oil change intervals - I'm intending to split the interval in half even though the $60 +time on my dime will be incurred on top of the BMW maint pkg - if I was intending to part company within a few years I probably wouldn't bother... I would also be hesitant to pickup a used unit as well even if the service intervals were followed. my 2cents