BMW modifies oil recommendation for M engines

[thekurgan]

I'm sure many have seen this by now, but I thought I'd bring it to light in the event some have passed it up.

Many are reading this as: " you now have a choice " ... apparently some dealerships are asking customers when they come in for M car service but I think those are ghost stories.

I read this like the owner's manual: if TWS isn't available, you are also allowed to use these now-recommended 5w-30.

The discussion at m3post is alluding to the tight clearances of the rod bearings, combined with the 60 weight oil, as to the early demise of the rod bearings. Also, the rod bearing was changed to a much harder material > 2011, but the clearances were not modified. BMW has done some interesting things here.

Either way, here's the information in case you haven't seen it.

[jdoublehcubed]

That is kind of strange, and I'm inclined to agree with you.

I'd really like to know why they went form 10w60 all the way to 5w30 as the alternate. There are plenty of weights in between. Mobil1 makes 5w40 for sure, and I think I've also seen Mobil1 10w40 and 5w50. Why not recommend those (obviously closer) weights? Do they really have that much loyalty to castrol?

[chickdr]

That makes no sense at all. Use 10W60 or 5w30? They are so far apart it isn't funny.

[David70]

The "only use Castrol 10W60 and no other brand of the same weight " seems really suspect when they also throw in that 5W30 Castrol is also allowed.

How much does Castrol pay for this?

[mtrhed]

So which oil should I use?

[thekurgan]

It seems the oil you may chose could very well depend on how the car is driven. The Ford mustang equipped with the track package calls for 5w-50, while the non track pack equipped vehicle uses 5w-20/5w-30 IIRC. There really is no difference aside from an oil cooler, unless someone knows of other mods to the track package in regards to the engine.

[mtrhed]

I was just joking!!!


But that's a good answer.

[Shipkiller]

Well, I use Redline 15W50. The engine runs cooler and for a side benefit I get 1-1.8 MPG better gas mileage on the highway.

I just got done pulling the oil pan to retrieve a valve shim. I also pulled an oil sample at the same time. This will be the first oil sample since I had my rod bearings changed 4000 miles ago... This starts the new baseline and time will tell.. I had nine track days on this oil.

[thekurgan]

Originally Posted by Shipkiller

Well, I use Redline 15W50. The engine runs cooler and for a side benefit I get 1-1.8 MPG better gas mileage on the highway.

I just got done pulling the oil pan to retrieve a valve shim. I also pulled an oil sample at the same time. This will be the first oil sample since I had my rod bearings changed 4000 miles ago... This starts the new baseline and time will tell.. I had nine track days on this oil.

For track use, as long as the oil stays warm, this could be a way to go as well. For city folks or non tracking, maybe BMW is seeing better bearing wear with thinner oil, such as during cold start. The thinner oil will also be able to release heat easier than the TWS.

[Shipkiller]

Heat is not the issue. On the street, the engine oil temperatures always stay between 195-200 even if ambient air is 99'. On the track, the engine oil temperatures stays between 200-215. ONCE I saw temps go to 220 but ambient air was 105'. The two different engine cooling systems are more than capable of removing the heat. This only goes for a normally aspirated engine. The reason for using a lighter viscosity oil (a 50 vs. 60) is that it flows better.

Also, in all the research I have done on engine oil for the S54 indicates that TWS is not as good as Redline and will actually shear down much faster than other synthetics.

Since most of use are not going to fix the main issue, that is the bearings are just too narrow, we are going to use band-aid fixes like coated bearings and different weights of oil.

[EMP07]

http://www.redlineoil.com/news_article.aspx?id=13

It's a vendor article but...

[David70]

I will stick with 10W60 as I haven't seen much of a reason to switch to some other weight. The idea that some have switched and not seen a problem doesn't me mean much to me. The sample size and data is lacking. I also don't see a lot of reason for BMW to initially require it if there wasn't at least a decent reason to do it.

I am considering switching to another brand as I haven't seen any proof that Castol is better than the rest. Yes BMW was part of the development of it but I think the best outcome possible was Castrol made the best oil they they could produce and it was satisfactory to BMW, doesn't mean others couldn't do better.

[thekurgan]

Originally Posted by David70

I will stick with 10W60 as I haven't seen much of a reason to switch to some other weight. The idea that some have switched and not seen a problem doesn't me mean much to me. The sample size and data is lacking. I also don't see a lot of reason for BMW to initially require it if there wasn't at least a decent reason to do it.

I am considering switching to another brand as I haven't seen any proof that Castol is better than the rest. Yes BMW was part of the development of it but I think the best outcome possible was Castrol made the best oil they they could produce and it was satisfactory to BMW, doesn't mean others couldn't do better.

I agree, Dave. I guess the question was why, after all these years, is BMW now allowing other LL-01 oils for M cars. Why have bearing surfaces been changed out for a harder surface? I can't see it as an environmental move.

[Shipkiller]

When the S54 was originally released, it used 5W30. It was only after the bearing issues was the specification changed to 10W60.

Here is the link to the spreadsheet data I was able to find (and is still looking for) on engine oil and trans/diff oil.
http://www.shipkiller.com:8080/10W60-Oil_Specs.xlsx

[beta]

To me the biggest question is, which oil is better to prevent bearing issues?

[Shipkiller]

Well, I don't think there is a 100% sure fire answer since the underlying bearing issue is a design issue (the bearings are too narrow), but I do not subscribe to the 'the BMW engineers know more than you' response.

In May at VIR, I had a discussion with James Clay (Bimmerworld) and he related to us standing around that they (Bimmerworld) has seen much better rod bearing wear by switching to 15W50 vice 10W60. Now this was primarily on the race cars but you could extrapolate the data back to a street car, and since they tear down their engines much more frequently than we do, they do have the data.

I had been thinking along these lines for a while now, but this new data was the push I needed to do the change. Since my rod bearings were just changed (4K ago) and I just pulled an oil sample, this resets all my data and I will be able to tell if it does any good or not.

[David70]

Originally Posted by Shipkiller

Well, I don't think there is a 100% sure fire answer since the underlying bearing issue is a design issue (the bearings are too narrow), but I do not subscribe to the 'the BMW engineers know more than you' response.

In May at VIR, I had a discussion with James Clay (Bimmerworld) and he related to us standing around that they (Bimmerworld) has seen much better rod bearing wear by switching to 15W50 vice 10W60. Now this was primarily on the race cars but you could extrapolate the data back to a street car, and since they tear down their engines much more frequently than we do, they do have the data.

I had been thinking along these lines for a while now, but this new data was the push I needed to do the change. Since my rod bearings were just changed (4K ago) and I just pulled an oil sample, this resets all my data and I will be able to tell if it does any good or not.

I'm always skeptical when I read something that someone else told them without anything to back it up, also doesn't make it wrong. I am interested in hearing how the oil samples go. As James Clay ever written (posted) his findings?

Seems unlikely to me that after 12 years of recommending the 10W60 (not sure on dates) that BMW engineers wouldn't have realized that the 15W50 works better, again speculation. Also, I generally prefer to follow manufacturers recommendations unless there is good data or proof showing something else is better. The whole "use Castrol only" is a little different because I don't believe they tested any brands that might be better because of this partnership.

[Shipkiller]

Originally Posted by David70

Seems unlikely to me that after 12 years of recommending the 10W60 (not sure on dates) that BMW engineers wouldn't have realized that the 15W50 works better, again speculation. Also, I generally prefer to follow manufacturers recommendations unless there is good data or proof showing something else is better. The whole "use Castrol only" is a little different because I don't believe they tested any brands that might be better because of this partnership.

From the research I have found, most people who were in the know back in the E46M3 bearing fiasco agree that after 1.5 years of production the move away from 5W30 to 10W60 was a band-aid fix for the bearing issues. The move to 10W60 just lets the motor get past it's 5/50 warranty period when BMW is not responsible anymore. We have seen enough proof of this in other areas of BMW engineering. I do not think it's the engineers making the decisions in regard to this. I would be willing to bet it's the marketing and bean counters.

I do not think there is a 'right' answer to this oil question. I just changed based on oiling principles and others who do know more than I do, not to steer me wrong. We shall see. The proof will be in the Blackstone reports. Of course, I do not subscribe to the 15K oil change intervals that BMW recommends either.

[Finnegan]

^ +1

Excellent reasoning and agree with the points noted. Since, as you say, it's a design issue we're really chasing options not total solutions (fix the crank/bearing/design).

[David70]

Originally Posted by Shipkiller

From the research I have found, most people who were in the know back in the E46M3 bearing fiasco agree that after 1.5 years of production the move away from 5W30 to 10W60 was a band-aid fix for the bearing issues. The move to 10W60 just lets the motor get past it's 5/50 warranty period when BMW is not responsible anymore. We have seen enough proof of this in other areas of BMW engineering. I do not think it's the engineers making the decisions in regard to this. I would be willing to bet it's the marketing and bean counters.

I do not think there is a 'right' answer to this oil question. I just changed based on oiling principles and others who do know more than I do, not to steer me wrong. We shall see. The proof will be in the Blackstone reports. Of course, I do not subscribe to the 15K oil change intervals that BMW recommends either.

I agree with the above, just think they had to have a reason to go to 10W60 which created more bad press with this odd ball weight. I remember reading about it at the time and thinking I had never heard of this weight and thought the solution seemed odd. I think it would have been simpler and the first solution to stick with a more conventional oil. I know if someone came to me and said we needed to use 10W60 I would have asked about other, more standard weights.

I also agree about the decisions not always being decided based on longevity. If longevity was the most important factor all car manuals would say "for maximum longevity use synthetic motor oil". I have never read anything that disputes this, only that the average consumer probably won't keep the car long enough for it to matter to them and that it costs more up front.

[Shipkiller]

Originally Posted by David70

only that the average consumer probably won't keep the car long enough for it to matter to them and that it costs more up front.

That........ no truer words have been spoken...

[VitaminT]

Interesting. At least it gives people options. For me, I put 135k on my E46M3 and my 06MR is up to 75k with the Castrol TWS doing 15k changes.

I am not at all saying that mid-cycle changes aren't good and that alternative oil options might not be better, but for me I will stick with what has worked mile after mile.