The major benefit is fewer intake valve deposits, and extended cat life. I am not fully up to speed on how much either is a problem on the N55.
BMW N55 - forced to choose something new
- Thread starter Craig in Canada
- Start date
The major benefit is fewer intake valve deposits, and extended cat life. I am not fully up to speed on how much either is a problem on the N55.
Valve deposits are an N55 issue although, like, an order of magnitude less than the N54. I have not installed a catch can so I am interested in this.
So now I suppose I have an actual choice on my hands -
1/ PP Euro L 5W30 LL-04 low SAPS
- potentially cleaner valves
- goes against BMW's recommendations for my engine and country
- can/must use UOA (checking TBN, specifically?) to verify if I'm OK or not
- Classic LL-01, recommended by BMW
- looks like a good alternative to Edge 0W40 - a little thinner and much warmer pour point (-57C Edge vs -36C PP)
- maybe more valve build up
It's still odd to me why BMW hasn't changed their recommendation. Is this true on the 2019, or maybe 2020 cars? My sister has a '17 Mini and even it calls for LL-14FE but says LL-17FE (the low saps equivalent) is acceptable.
The TIS article which I linked is from early 2019, and you can see that several engine models have non-LL01 recommendations listed. For the B58 and B48 without PPF, for instance, LL17-FE+ is the preferred oil. N55 remains LL-01 outside of EU.
I would think that if the US ULSG and Canadian Jan 2020 sulphur specs were low enough for them they would change some of the LL-01s to LL-04 for Can/USA.
I guess that even though spec approval isn't vital to me, I'm not necessarily confident enough to go low SAPS against recommendation without knowing exactly what I'm getting into. Am I fine as long as a TBN/TAN test in UOA says I did not exhaust the oil? Is that my only risk of going low SAPS? If that's true, then I'm extremely unlikely to see an issue with my relative short (for the quality of oil used) OCIs.
Here in the US at least, while we are under the Tier 3 EPA mandate it does not mean that all fuel is of the same sulfur level. There are time extensions for small refiners and others, and so although overall the level is lower it does not necessarily mean any one purchase or region is as low as another.
Euro sulphur levels are at 10 mg/kg. Here they are 12 mg/kg, not a whole lot of difference. Five years ago they were 4-5 times that high, or even more. In fact we have been on lower sulfur fuels for longer than the USA has, we are ahead of them in this regard. If you read the link earlier it says 12 mg/kg is the goal but some refiners will go on a pool average which can allow up to 80 in one batch but the average must be under 10. So if they choose that option you may have a batch at 80 but then you'll have twenty batches at 7, for example.
The sulphur turns the oil acidic faster, so you need higher TBN to combat that. The full saps oils have TBN around 10-11 usually, the low saps it is more like 7.5-8. So, in a high sulfur fuel environment the oil will become acidic faster.
Keep in mind however, the low saps oils are approved for double the oil change interval in Europe. Now, this is true with VAG, I am not 100% sure BMW is the same, but I imagine they are. The full saps stuff is 15k (km) or one year, the low saps is based on the vehicle OLM which can be up to 30k or two years. So in low sulfur environment the long term viability of low saps oil is absolutely no concern.
I suspect BMW may be concerned with ethanol content in fuel here which is why they still use full saps. I believe in western Europe it is not really normal to have 10% ethanol.
I have a 2018 RS3 and as I said before it is the first engine in North America VAG approved for use with low saps oil, it is the only recommended spec for the car. The normal service interval is 15k, I only drive about 12k per year so I typically do that. Starting in 2019 low saps oils (504, 508) went across the entire range.
Another thing to consider is the low saps oils stay in the TBN range of about 2-3 for a long, long time. They do not drop linearly. So if you have a starting TBN of 8, do a TBN check at 10k km and it's at 3, it doesn't really tell you much other than OCI of 10k is very safe. The oil could take another 10k to fall from 3-2. I can't explain why it does this, I am not a chemist, but this phenomenon has been consistent with low saps oils for many years now.
IMO you have absolutely nothing to be concerned about with LL04 especially with your service interval of 6-9k. If the car burns any oil I would also be more inclined to use it because of the added benefits and you're also adding TBN back in with new oil.
Last edited:
I should clarify, I keep saying low saps above but it is more like mid saps, usually about .8 or so. Full saps usually about 1.1-1.3.
Great post - thanks for the wealth of information. This isn't keeping me up at night - I just want to choose something and move on. A catch is that I may be interested in defying BMW and going low SAPS in the interest of valve cleanliness as long as I know the "dangers" and exactly what to watch for.
I thought valve cleanliness was more a NOACK thing? Off to google...
Anytime you can either reduce oil mist in the crankcase (lower noack) or reduce the contaminants in that mist (lower saps) it will help reduce intake valve deposits.
There is another theory as well that new oil is more volatile than older oil and as such will lead to more carbon buildup if you change oil more often. I don't know if that has actually been proven yet or not though.
LOL Well I'm in trouble then. Short trips, cold climate, full SAPs, Edge 0w40 Noack something like 11, change oil frequently. Doomed...
I'm going to go see what folks have done for catch cans too - should have done it years ago I guess.
Castrol 0w40 is discontinued in Canada. I scooped up all that I could track down.
I've never heard of bearing issues with N55, just because I haven't heard it doesn't mean it's not there.
Your choices are really Castrol 5w40, Penn Euro, supertech Euro 5w40, Mobil 1 0w40 ( you don't want to use) and Canadian tire brand ( shell). It sounds like you don't want the Castrol 5w40 which means you probably won't want the supertech 5w40 either. You have stated you don't want Mobil 1 so it looks like Penn Euro or Canadian tire for you.
I've never heard of bearing issues with N55, just because I haven't heard it doesn't mean it's not there.
Your choices are really Castrol 5w40, Penn Euro, supertech Euro 5w40, Mobil 1 0w40 ( you don't want to use) and Canadian tire brand ( shell). It sounds like you don't want the Castrol 5w40 which means you probably won't want the supertech 5w40 either. You have stated you don't want Mobil 1 so it looks like Penn Euro or Canadian tire for you.
There are also boutique options from a place like germanparts, they have LM, Total, Fuchs, Motul. Of course they are probably no different in terms of performance, but it's another option.
The OP stated " I would prefer something I can get at normal retailers that I can scoop up on sale as opposed to boutiques, special orders and lots of effort to get my hands on it."
Fair point
Some N51, 52, 54 and 55 develop it. Mostly related to pushing engine too hard before reaching operating temperature.
I currently own a M54, two N52, a N54, a N55 and a 63. As I stated I have never heard of bearing issues with these motors. Perhaps I have not looked deep enough to find some complaints about bearings. All of these motors have their issues but I haven't heard much about bearings. I guess I've been lucky lol.
It is highly uncommon, but it happens, and interestingly happens at relatively low mileage.
But once you dvel into it you see gross negligence by owners.
