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

Joined
Sep 4, 2015
Messages
818
Location
Munich, Germany
Gentlemen,

until now, my gospel for buying an oil - in this case my Honda S2000 - was: Gasoline Oil for gas engine, reputbale brand, correct viscosity (Very important!), MB229.5 and Porsche A40 approval, prefered GTL / Group IV and i call it a day. But recently, i was wondering... Could it be that the newer generation of Diesel Oils outperform the older MB 229.5 / Porsche A40 gasoline oils?

Just a example, Ravenol did recomend their VMP 5w-30 on their German homepage as 2. Choice for the Honda S2000. This oil is clearly aimed for Diesel passenger cars, it carrys Acea C3, MB 229.51, Porsche C30 and VW 504 00 / 507 00 approvals.


Playing around with his tool https://online.lubrizol.com/relperftool/pc.html i found out to my surprise that the VW 504 00 / 507 00 spec has a higher rating for wear protection compared to their MB229.5. Thinking about it further, less deposits in the combustion chamber, pistons and vlaves from Low / Mid Saps oil is not a bad thing for a engine that burns some oil.

Thoughts? It is time to think new?
 
MB229.5 or porsche A40 are NOT gasoline oils, they are A3/B4 oils and are DUAL RATED gasoline/diesel oils.

ACEA C oils are also dual rated, the mid saps is not meant for diesels but for exhaust treatment equipment.

And you are using the lubrizol tool wrong, it's not meant to compare between specifications, but rather what each specification focuses on.

Have you ever found ash deposits in a combustion chamber? I've found carbon deposits, but those come from incomplete combustion, can be from gasoline, diesel, lpg, or engine oil.

I've not seen C3 oils outperform A3/B4 oils, or out last I should say. The extra TBN and oxidation resistance from extra calcium/magnesium and zddp goes a long way if the base oils are of equal quality. Cheap A3/b4 will be made from group III oils, but so is cheap C3.
 
Donald, thanks for the hint. you are right, one have to selcet carefull today. I was aware about this.

Jetronic, thanks. My Impression was: MB 2295 / Porsche A40 / ACEA A/B: Gasoline. MB 229.51/ Porsche C30 / ACEA C: Diesel.
Thanks for the hint about the lubrizol tool. It is called a "performance" comparison tool?
Regarding the depostis, a Low / Mid saps oil schould leave fewer deposits in the combustion chamber, at least that´s what the internet says...

I am still puzzled why the Oil selecting tool of some oil Manufacturers sometimes show diesel oils for the S2000 when the companys have some MB 229.5 / Porsche A40 Oils in their product catralouge....
 
Those ACEA C3/VW 504 00/507 00/Porsche C30 oils are certainly proper choices for the correct application. Does your S2000 actually require 30 weight oil? If 40 weight is fine, I'd seriously consider VW 511 00/Porsche C40.
If you want Ravenol, for an S2000 I'd go either REP or RUP instead of VMP. Just a maginal price difference, but even better base oils and add pack (Vanderbilt Vanlube W-324 > liquid tungsten).

Btw, VW 504 00 is a gasoline engine approval and same applies to both VW 511 00 and Porsche C40.
 
Those ACEA C3/VW 504 00/507 00/Porsche C30 oils are certainly proper choices for the correct application. Does your S2000 actually require 30 weight oil? If 40 weight is fine, I'd seriously consider VW 511 00/Porsche C40.
If you want Ravenol, for an S2000 I'd go either REP or RUP instead of VMP. Just a maginal price difference, but even better base oils and add pack (Vanderbilt Vanlube W-324 > liquid tungsten).

Btw, VW 504 00 is a gasoline engine approval and same applies to both VW 511 00 and Porsche C40.

Yes. The S2000 actually requires -30 Oil. -40 oil only if the temperature is below -20°C / -4°F.
If you are puzzled now, that is what the owners manual says and that´s what puzzles S2000 owners ever since.

The bearing tolerances etc. are on the thight side, this engine is clearly designed for -30 or a thin(!) -40 Oil.

Yes, i know that REP or RUP are better choices, i was just playing around with the "Oil selector for your car" tool at the Ravenol Homepage and was wondering about the reccomendation that comes up, a diesel oil... :unsure: i was stumbling about this on other Oil Companys Homepages as well.

Thats why i start to wondering if this oils are superior to MB 229.5 / Porsche A40 oils. Since i dont cared about this new diesesl oils and VW specs before, i just dont realised that some ratings are dual for Gasoline and Diesel.
I was contrarary minded.
 
REP is at the thicker end of 30 (which is common for VW 504 00/LL-04/MB 229.51) and has a pretty solid HTHS of 3.7 mPas, while RUP is on the thinner end of 40, probably just necessary to meet the fuel saving requirements of BMW LL-04 and MB 229.51 and perhaps also Porsche C40 & VW 511 00. Not that of a huge difference in real world. They're d a m n close.
 
Yes, i have discoverd that some -40 oils are very thin, between 12.5-13.5 KV 100. Almost 30s...
I think i will stay with my Mantra: The oil for my S should have a MB 229.5 / Porsche A40 approval.
 
Long before manufacturer specific specifications were developed, 15W-40 HDEO was pretty much the "default" standard, including applications like air cooled Porsches. However, times have changed significantly and a one-size-fits-all oil is no longer the golden standard.

That being said, if you are already using an oil that has MB Sheet 229.5 approval, unless you are looking to decrease your drain intervals and are looking for a conventional or synthetic blend that is more affordable, I would stick to what you are using.

Taking gasoline quality into consideration, you could probably use an MB Sheet 229.51 oil with no issues. But, from a personal perspective, as long as a 229.5 approved lubricant is available, that is what I would use.
 
Not sure if I'd recommend FDS with HTHS of just 3,0 mPа*s for an 8000rpm S2000, Johnny.
I could be wrong though, if Honda uses similarly low HTHS oil. Honda's recommendations
seem odd enough.
 
Mine is 9000 RPM redline, the early one. ;)

Honda just specd a 10w-30 for this engine back in the year 2000 and that´s it. HTHS of this viscosity is around 3 - 3.2? The engines run forever with this Viscosity in the USA, there are several examples around that have 300 000 Miles on the first engine and still going.

I just want to have a HTHS around 3.5 for a little bit extra protection. I think my driving style here is a little bit more demanding.
The discussion, articels and so on here about Minimum film thickness and bearing clearances are very interesting. All prooves that Honda was right. (Of course they where right....)

I think the worst you could do is to use a thick -40 or high HTHS oil in this engine and then drive it hard on the Autobahn.
 
While I'm aware of thicker oil causing more drag, what else does reasonably thicker oil do?

.
I suppose the answer would depend on the engine. Or maybe that was a rhetorical question?
I tried 10W60 in the Barchetta (a 40 is recommended) and noticed higher oil temperatures. Some users noticed more wear on camshafts with thicker oil, that part I suppose because the oil was never brought to full temperature before hard use.
I'm using a 40 in my Mazda where a 5W20 is recommended and only noticed less noise, but then again the European recommendation for that same car is 5/10W40. I seriously doubt that engine cares...and it's never overly stressed either on our "roads" full of potholes and "highways" limited at 100Km/h.

For a S2000 taking 8/9000rpm, maybe there's a different answer.
 
Back
Top