Oil questions, old Mercedes engine

[vivaUkraine]

*1993 Mercedes 400E, 127,xxx miles. 4.2L, V8 (M119). Owned for 6 years, plan to keep indefinitely. Daily driver, currently 12k/yr. No oil leaks. OCI 5-7,5k mi. Been using various synthetics over the last 28,000 miles, since I acquired her. I drive in a very brisk, but (mostly) mature manner. Hot and humid summers. *Original manual calls just for whatever API was current in 93 and 10w40, 15w40, 5w50, 20w50 for all temps. There's a 5w30 in there for up to 30C ambient, if it has a precursor to A3/B3 spec. So I'm aware that, technically, using today's lowly 10w40 dyno SN will exceed factory requirements. I'm also aware of the Walmart Mobil/Castrol 0W40 thesis. With the above out of the way, I'm curious: 1. Is 229.5 oil there most optimal choice for an engine developed in the 2nd half of the 80s? Any merit seeking out 229.1 or 229.3 oils? 2. Castrol has a 0w30 with a 229.5 certification, which means it has same HTHS as 0w40 and 5w40 229.5 oils. Would this not be the most optimal choice, given same protection as heavier grades, but with some, however minuscule gains in fuel economy and power? 0w30 is not in the original manual, neither is 5w40 and 0w40, but it's been 27 years since... 3. Is there any merit in using synthetic high mileage 10w40 oils that don't have any manufactures certifications instead of 229.1/3/5 oils. Again, there aren't any oil leaks. Thanks!

 

[Silk]

10W-40 A3/B4.

 

[userfriendly]

API CG-4 was rolled out in 1994. Back then 15W had to pass CCS at -15C and cold viscosity @ -20C. Now 15W is tested where 10W used to be. At -20 & -25. If a modern CK-4/SN oil was available in 1993, weather permitting it would have been revolutionary. Especially given that the cost has remained the same over the years. When I joined this group, I had a 1 year old MB C240. I got tired of paying $13 a liter for M-1 0w40 and used 15w40 instead at a quarter of the cost. The next summer I tried SAE50, just to prove to the thinnies here, that it wouldn't cause the sky to fall or kill off the whales. If I had to pick one oil for all seasons, and cost was no object, I would use the same oil I'm putting in 2 Duramax engines this fall. Chevron's Delo 400 5W40 CK-4 with an HTHS of 4.2

 

[ChristianBerg]

If the engine isn't burning oil, I'd stick with any 10w40 syn blend with the best API possible, even better if you find one with MB approval. I think anything above that is a overkill.

 

[Ignatius]

I like to used Mobil 1 0w40 in my 2005 Mercedes engine because it meets 229.5, is relatively inexpensive, and can usually had with a rebate or some other promotion. Valvoline makes some very nice oils carrying most high level approvals like 0w40 and Euro 5w30 and Euro 5w40.

 

[ka9mnx]

Originally Posted by Silk

10W-40 A3/B4.

This or 0w-40 A3/B4

 

[Astro14]

I owned a similar vintage 300E for many years. The W124 body is one of Mercedes best built cars, ever. My preference is for an MB 229.5 spec oil. Several inexpensive options exist: Castrol 0W40 ($22/jug on Amazon) MOBIL 1 0W40 ($25/jug at Walmart). I also used Rotella T6 5W40. Similarly priced to the above, and while it doesn't have the MB 229.5 spec, it's a very good oil. When I did the head gasket on that car (a regular 100,000 mile service on the M103 engine) it was spotless. Absolutely spotless. Here it is on the bench. So, when the 229.5 spec oils are as cheap as anything on the market, I can't see a good reason for using anything else.

 

[BAJA_05]

PP Euro 0W40/Mobil 1 0W40/Castrol 0W40 -- which ever is cheapest and lose zero sleep!!!

 

[Gene K]

Just my opinion but you could do a lot worse than Rotella 15W-40 Summer and Rotella T6 5W-40 Winter.

 

[Jackson_Slugger]

M1 10W-40 HM in summer/warmer months, any 0W-40 in winter...

 

[ka9mnx]

Which I believe is A3/B3. Perfectly fine.

 

[vivaUkraine]

Thanks. So there isn't any merit seeking out a 229.3 (or 229.1) oil over 229.5, in your opinion? Are 229.5 oils in different viscosities same and interchangeable in my application, irrespective of climate? Like Castrol 0w30 and Mobil 0w40 and, say, Liqui Moly 5w40? My thinking - I could easily be wrong - is that if 229.5 oils are indeed interchangeable and offer same protection, a 0w30 grade offers the same protection as 0w40 and 5w40, but might offer a slightly better fuel economy and power, no? My current fill is Mobil 5w50 fs x2, which has 229.1 and 229.3 certifications and, as far as I can tell, is the only modern oil in US to do so. Thanks

 

[Linctex]

Originally Posted by Silk

10W-40 A3/B4.

Yes. If you aren't emotionally married to the car, I'd run the cheapest 15W-40 HDEO that any tractor supply business sells for cheap.

 

[Linctex]

Originally Posted by Astro14

When I did the head gasket on that car (a regular 100,000 mile service on the M103 engine)

How bizarre is that...... I never pull the head unless there's a good reason to.

 

[vivaUkraine]

Many of you answered with specific brand recommendation. My questions were regarding Mercedes certifications and a merit (or lack of) in seeking older certification for my old engine AND a merit in using 229.5 0w30 vs 229.5 0/5w40 oils in all climates. It's not clear to me if different viscosities of 229.5 oils are identical and interchangeable, irrespective of the climate....

 

[barryh]

Originally Posted by vivaUkraine

Thanks. So there isn't any merit seeking out a 229.3 (or 229.1) oil over 229.5, in your opinion? Are 229.5 oils in different viscosities same and interchangeable in my application, irrespective of climate? Like Castrol 0w30 and Mobil 0w40 and, say, Liqui Moly 5w40? My thinking - I could easily be wrong - is that if 229.5 oils are indeed interchangeable and offer same protection, a 0w30 grade offers the same protection as 0w40 and 5w40, but might offer a slightly better fuel economy and power, no? My current fill is Mobil 5w50 fs x2, which has 229.1 and 229.3 certifications and, as far as I can tell, is the only modern oil in US to do so. Thanks

You will be lucky to find any other oils to the 229.1 spec and there is no advantage in seeking out that older spec. The newer specs are better oil. When i ran an MB of that age I used any 5W40 that met 229.3 or Acea A3/B4. All MB oils of this type meet Acea A3/B4

 

[kschachn]

Originally Posted by vivaUkraine

It's not clear to me if different viscosities of 229.5 oils are identical and interchangeable, irrespective of the climate....

Who said irrespective of the climate? If you are starting at temperatures below -35F then there would be reason to use an oil with a 0W winter rating, If not then there is no difference. And with a minimum HTHS of 3.5 the differences in the operating viscosity will be truly irrelevant.

 

[vivaUkraine]

Originally Posted by barryh

Originally Posted by vivaUkraine

Thanks. So there isn't any merit seeking out a 229.3 (or 229.1) oil over 229.5, in your opinion? Are 229.5 oils in different viscosities same and interchangeable in my application, irrespective of climate? Like Castrol 0w30 and Mobil 0w40 and, say, Liqui Moly 5w40? My thinking - I could easily be wrong - is that if 229.5 oils are indeed interchangeable and offer same protection, a 0w30 grade offers the same protection as 0w40 and 5w40, but might offer a slightly better fuel economy and power, no? My current fill is Mobil 5w50 fs x2, which has 229.1 and 229.3 certifications and, as far as I can tell, is the only modern oil in US to do so. Thanks

You will be lucky to find any other oils to the 229.1 spec and there is no advantage in seeking out that older spec. The newer specs are better oil. When i ran an MB of that age I used any 5W40 that met 229.3 or Acea A3/B4. All MB oils of this type meet Acea A3/B4

I can easily and at about the same price source 229.3 and 229.5 oils. Castrol 5w40 here in US has a 229.3 spec, but not 229.5. Plenty of 229.5 oils in 0/5w40. If there's isn't any merit in using older 229.3 spec, then why the [censored] Castrol has this oil? It ain't any cheaper. I'm trying to capture the underlying logic...

Originally Posted by kschachn

Originally Posted by vivaUkraine

It's not clear to me if different viscosities of 229.5 oils are identical and interchangeable, irrespective of the climate....

Who said irrespective of the climate? If you are starting at temperatures below -35F then there would be reason to use an oil with a 0W winter rating, If not then there is no difference. And with a minimum HTHS of 3.5 the differences in the operating viscosity will be truly irrelevant.

If 229.5 0w30 is good for any climate, then why does 229.5 5w30, 0w40 and 5w40 exist? What's the logic there? They are all about the same price. Do you happen to have an explanation? Thanks

 

[kschachn]

Originally Posted by vivaUkraine

If 229.5 0w30 is good for any climate, then why does 229.5 5w30, 0w40 and 5w40 exist? What's the logic there? They are all about the same price. Do you happen to have an explanation? Thanks

Because the approval requires a minimum HTHS of 3.5, it could be slightly higher. But more than that the grade designation isn't the most accurate way to specify the operating characteristics of the oil, HTHS is better. And an oil that tests out with the required HTHS may fall into different grades per the different ASTM test. https://360.lubrizol.com/2019/Visco...s-the-Difference-and-Why-is-it-Important

Originally Posted by Lubrizol

It's important to understand that engine lubricants can have the same viscosity grade but different HTHS viscosity.

And the converse is equally true. An oil with a specific HTHS can have a different grade. It's not about "logic" or marketing, it is about the specifics of each test. But the bottom line is that unless the winter rating is important to you then any of those oils that carry the required approval will operate virtually the same in your engine.

 

[vivaUkraine]

@kschachn, thanks, your answer hit into the center of core.