New passenger car diesel oils = Better protection for older gasoline engines?

I doubt Supertech is sold in Munich. No need to hassle with Volvo approvals. Plenty of choice on BMW, MB and VW or even Porsche approved oils in Germany.
Did I mention Porsche? Ravenol RUP got BMW LL-04, VW 511 00, MB 229.51 and Porsche C40 approvals. Hard to beat. That's probably what I'd try in this S2000 first.


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Hmm... So you suggets that this beat the 229.5 approval of the RSP? :unsure:
 
I spoke to Castrol about that years ago, I was getting the RS MC from Louis for DM25 for 4 ltr and wanted to use it in my E30 M3 with S14 engine. They said it was no issue whatsoever, it is not different than using a diff oil that contains a limited slip additive in a non LS diff.
They basically said do do the opposite (car oils in MC) although many people use car oils in MC seemingly without any issues.

When I think about it, what is the difference? Both have a crank, cam(s), cam chains, oil pump, rocker arms, lifters/ lash adjusters or shims.
The car engine is missing the wet clutch and in most modern bike engines the gear box.
I ran my brand new SC24 Euro spec out of Holland still in the crate (Germany still had a 100HP limit at that time thanks to the CBX), I broke it in on dino slowly (not over 4K rpm per owners manual for the first 400km) for the first 1K then switched it over to RS, it never had any other oil or any other rider.
I ran it over 240K km over 12 years and ran hard, lots of high speed Autobahn use, at 240K I did the cam chain which required splitting the cases, no bearing scoring or cylinder wall wear, all measurements were in new engine spec according to the FSM.

Imagine that on a 10w60 of all things, the transmission and long term high rpm really beat the oil up bad which is not an issue with your car, no need for an oil that heavy.
The engine had a min oil pressure of 7bar. The 4 cyl M3 never had any issues, it ran for many years on the RS without complaint, its bearing clearances were designed for heavy oil.

You are right, what is the difference? In my opinion it is more likely that the Motorcycle oils have the better (=More Expensive) VI Improvers, needed in motorcycle engine to withstand the stress in a gearbox. But the problem is, that the Chocie of -30 Viscositiy is VERY limited for Motorcycles, while i have a big selection of -30 oils for Cars, up to really PAO + Raceworthy oils.
 
The last two reports about damaged engines in the german S2000 Community had two things in common:
Both owners tried to reach top-speed of the car on the autobahn and both used -50 (!) oil.

I trust the engineers at Honda, i will use a thick 30 - thin 40 Oil, viscoity range 11-13 KV 100°. And i will never press the car to the limit on the autobahn, i am convinced that this engine is not safe for long time full throttle runs because of the insane piston speed at 9000 RPM.

Christian, have a read on the following:

No engine, ever has been damaged by using an oil with a higher grade than what is recommended. You know why they word it that way in the manual, right? It's not for a mechanical reason.

Plus comparing an approval with all the manifold requirements for things other than viscosity is not meaningful. If you use an oil without the proper BMW approval but with the required minimum HT/HS then the grade isn't going to be what causes a problem.

As a bottomline, I'm very much under the impression, you're somewhat overthinking your oil choice.
Some 5W-30 too thick? That's not going to happen. Some on the thinner end 5W-40 too thick?
Unlikely. Did you record oil temperatures already? Actual viscosity depends on oil temperature.

Regarding differences between MB229.5 and MB229.51: Except for sulphated ash, phosphorus and
TBN requirements they're practically identical according to Afton Specification Handbook 2018.
Quite marginal differences for piston cleanliness, SRV test, fuel economy tests and oxidation limits.
If at all I'd say there are minor advantages for MB229.51. Both are tough specs anyway. Honestly,
there's simply no reason to lose sleep over it.

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Thanks for your Reply. I think my posting about viscosity was a little bit vague. I think a thin -40 or thick -30 is perfect for the S2000, while a - 50 is way to thick. Maybe even a thick -40 is to much.
Where could i learn more about these new (to me) Diesel or dual Gasolin-Diesel specifications like the MB 229.51? And who could i compare them to - lets say- the MB 229.5 and Porsche A40?
 
Thanks for your Reply. I think my posting about viscosity was a little bit vague. I think a thin -40 or thick -30 is perfect for the S2000, while a - 50 is way to thick. Maybe even a thick -40 is to much.
Where could i learn more about these new (to me) Diesel or dual Gasolin-Diesel specifications like the MB 229.51? And who could i compare them to - lets say- the MB 229.5 and Porsche A40?

You can't really compare them as you only know if an oil passed the test, but not how well it passed. And an oil that doesn't carry the cert might or might not pass, it's part of the marketing structure that top dollar oils have the certs and the more budget oils not.

In other words, back in elemantary school if you scored straight 5/10 you passed just the same as the kid that got all 9 or 10/10....
 
Thank you all! I was doing a search for the "Afton Handbook" and found it. Oh boy, plenty of information. (y)
I learned that i can use also a MB229.51 or Porsche C30 specification.
Will think about it .
 
You can't really compare them as you only know if an oil passed the test, but not how well it passed. And an oil that doesn't carry the cert might or might not pass, it's part of the marketing structure that top dollar oils have the certs and the more budget oils not.

In other words, back in elemantary school if you scored straight 5/10 you passed just the same as the kid that got all 9 or 10/10....
So how do you determine what is good? So if an oil has an MB 229.51 approval how do you know which brand is good or it does not even matter?
 
You can't really compare them as you only know if an oil passed the test, but not how well it passed. And an oil that doesn't carry the cert might or might not pass, it's part of the marketing structure that top dollar oils have the certs and the more budget oils not.

In other words, back in elemantary school if you scored straight 5/10 you passed just the same as the kid that got all 9 or 10/10....

Or, like in grad school when I got an A+ average and was invited to join honors society - for a big fee of course - so I could claim I was a member. But I declined and saved the pointless fee. But that invite was also extended to my peers who scored an A- and paid for the honors society membership. I can still tell people, with proof, that I was invited and qualified to join.
 
Look for the oils that go "above and beyond"... If the norm is grp III base oil, look for one with a lot of PAO
I agree with the principle, but in what way does that demonstrate quantitatively better performance (performance meaning engine durability or efficiency or the like, not ‘spec-sheet racing’ which translates to nothing in service)?

It appears to me that European oil specs are no different from Japanese or American oil specs insofar as they do offer an incentive to be minimally-passing, but no incentive to exceed. The European auto industry has certainly succeeded in fracturing their market to a FAR greater degree than the American market. That’s far more profitable, but not demonstrably better for the consumer.

To put it another way, the specs set a minimum and encourage (profit incentive) marketers to not go beyond it any more than necessary to ensure a pass. This largely results in all the certified products performing basically the same.

Or, if this is not the case (after all, I may be wrong), how does one discriminate? An SDS can’t tell anything pertinent, I don’t think. If it can, how?
 
Good question. There's probably only alternatives: Either following the "all the certified products performing basically the same" theory or believing in "data sheet racing". Personally I tend to believe lower Noack, higher flashpoint and lower pourpoint are desirable. There's definitely substantial differences between PCMOs with same approval, so there's at least some who do more than minimum and just passing approvals.
 
Good question. There's probably only alternatives: Either following the "all the certified products performing basically the same" theory or believing in "data sheet racing". Personally I tend to believe lower Noack, higher flashpoint and lower pourpoint are desirable. There's definitely substantial differences between PCMOs with same approval, so there's at least some who do more than minimum and just passing approvals.

Yes but they generally cost more, and are therefor not competitive on the shelf of the store.
 
930, I’m certainly sympathetic to the notion that those things ‘should’ make a difference, but a difference in what? How? Let me give an example:
PUP has (or has generally had) a _higher_ Noack number than PP in the same grade, and sometimes even higher than yellow-bottle Pennzoil in the same grade. People generally believe PUP to be ‘better,’ though.
So, is everyone wrong about PUP being better than PP or PYB, or does the notion of lower Noack being better have far too many qualifiers to be a useful comparison number between lubes?
This same example applies (or has applied) to flashpoint when comparing across some brands (or maybe I should say blenders?).
Those spec-sheet items _might_ make a difference, but they’re just bench tests. What fired engine wear tests quantify their advantage, and does anyone at all display actual results of their product from those fired engine wear tests?

Maybe I’ve spent too many years trying to turn bench science or proxy tests into mass-production results, but I don’t find that stuff nearly as compelling as I once did.

I’d _really_ like to figure out (or to be shown is just fine) exactly how I’m wrong about that, though.

***EDIT:
Here’s a decent video about how we are often distracted and purposefully mislead, including by companies trying to sell nothing as something:

Check out the bit about how a 1% reduction in heart attacks by a statin drug is claimed as a 36% reduction.
 
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PUP has (or has generally had) a _higher_ Noack number than PP in the same grade, and sometimes even higher than yellow-bottle Pennzoil in the same grade. People generally believe PUP to be ‘better,’ though.
So, is everyone wrong about PUP being better than PP or PYB, or does the notion of lower Noack being better have far too many qualifiers to be a useful comparison number between lubes?

That's pretty much why I said this:

Personally I tend to believe lower Noack, higher flashpoint and lower pourpoint are desirable.

Keyword is "desirable". My primary starting point for oil selection is the required approval,
then other approvals, performance numbers and VOAs and UOAs. There isn't a single one,
most certainly for anyone here.
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My S2k was terrible on the Autobahn w/ 4.77 gears. Like 5k RPM @ 130kph.

Looking back, I think a 40 would have only helped.
Thats like cycling a bmx bike at almost top speed on the highway. Pedal fast, moving slow. My Toyota does 190kph at 5K rpm, same engine displacement. But I guess that's why they call the S2000 a "fun" car.
 
Thats like cycling a bmx bike at almost top speed on the highway. Pedal fast, moving slow. My Toyota does 190kph at 5K rpm, same engine displacement. But I guess that's why they call the S2000 a "fun" car.
My M5 did 290Km/h at ~6,000RPM ;)

Yeah, that S2K doesn't sound overly enjoyable at Autobahn speeds.
 
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