Conventional in bmw n54 for 60k kms

Please see attachment
3.7 is the number for the 20w-50

(Grain of Salt: I just found this sheet is from late 2012 though, but it already covers the SN, SM and SL formulations which are fairly recent certs.)
View attachment 265013
certs
20w50 is 4.6
10w30 is 3.2
10w40 is 3.7

I think it was overkill that once said that Castrol might as well have a picture of a pony on their PDS.
 
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20w50 is 4.6
10w30 is 3.2
10w40 is 3.7

Are you sure that is not just Min. HTHS. And not typical or Max. Strange table anyway.

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Are you sure that is not just Min. HTHS. And not typical or Max. Strange table anyway.
It is just the minimum HTHS required by J300. Castrol does this all the time. Most of those specs for CCS, MRV, pour point, and flash point aren't real specs either.
 
20w50 is 4.6
10w30 is 3.2
10w40 is 3.7

I think it was overkill that once said that Castrol might as well have a picture of a pony on their PDS.
These numbers admittedly make more sense then the ones I found.
but if anything, it supports my original point even better:

The oil might be Dino oil, but since it was on the thicker side it sitll protected comparable to some of next viscosity down in thickness synthetics.
Thicker also means better oxidation resistance, critical with turbos.
Back in the day when Dino oil were the standard, we would all run 20w-50 in any turboed application.
 
These numbers admittedly make more sense then the ones I found.
but if anything, it supports my original point even better:

The oil might be Dino oil, but since it was on the thicker side it sitll protected comparable to some of next viscosity down in thickness synthetics.
Thicker also means better oxidation resistance, critical with turbos.
Back in the day when Dino oil were the standard, we would all run 20w-50 in any turboed application.
That's back before OE approvals were a thing and forced manufacturers to blend better oils. Since 20W-50 has no OE approvals, it's probably cheap Group I/II with a decent slug of VII polymer.

Mobil Delvac 1 0W-40 has an HTHS of 4.1cP if that provides some perspective.
 
That's back before OE approvals were a thing and forced manufacturers to blend better oils. Since 20W-50 has no OE approvals, it's probably cheap Group I/II with a decent slug of VII polymer.

Mobil Delvac 1 0W-40 has an HTHS of 4.1cP if that provides some perspective.
Yep. Field reps that frequent mines and other industrial sites want the oil to be in grade at drain time to avoid lubricant warranty claims.
That’s why I plug that oil even though it’s out of my price range.

Add; Duckless, Those BMW and MB Diesels could probably use an EGR delete.
 
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Oof. I think you may have "gotten away" with it with the short intervals but it's surely not ideal. Check for sludge next time you pull the valve cover
 
That's back before OE approvals were a thing and forced manufacturers to blend better oils. Since 20W-50 has no OE approvals, it's probably cheap Group I/II with a decent slug of VII polymer.

Mobil Delvac 1 0W-40 has an HTHS of 4.1cP if that provides some perspective.
Here the new version is a API SP A3/B4 Syn Blend, i assume Group 2/3.
But yeah, the data sheet and the description of the oil on the TDS is pretty lacking as expected from Castrol.

Screenshot_20250224_080815.webp
 
Price/performance wise you have to go syn.

Seems like it's getting harder and harder to find dino in my area. Syn-blend is the worst i can do. Out of curiosity, i was checking the "inferior" oil section (the very bottom left shelf that you have to bend at an angle to see) ... and only saw 1 qt bottles. Castrol dino was $8.50+/qt. I assume I can buy Amsoil or HPL for that price. lol

Not long ago I bought 5 qt jugs of Castrol Euro with bunch of fancy Euro approvals for $24.xx. Not paying $8.50/qt for dino with only "it's oil" approval. :ROFLMAO:

FYI
I was checking the dino section recently for fun because my generator said to use Conventional 10W-30 for the break in period.
 
I would agree for that particular engine synthetic is the best option.

Here it's still easy to find conventional 15W40 or 20W50 PCMOs and HDEOs.

But the price difference now is much narrower between conventional and Syn Blends.
 
The 335d was too light for M57 in the US, where you can’t properly exercise it. I had tbat engine in X5 here where it didn’t have as bad issue as in E90. I had also M57 in Europe where hitting 130-140mph was normal and never had CBU issues. Sold car with 425,000km.
I remember many thought the difference was due to the implementation of EGR. Yhe X5 had high and low pressure EGR. The e90 only had high pressure EGR. *Shrug*
 
I've been using conventional 10w40 castrol gtx and a litre of motomaster 5w20 for the past 60k kms since I had the car, I didn't know I needed synthetic.

The car is running fine it is stock and not driven hard.

Have I done damage?
The N54 is a big fuel diluter. I remember UOAs showing the oil falling dangerously out of grade in only 2k miles. 10w40 will meet the minimum HTHS of 3.5cP. I would not go longer than 3k miles (5k km) or 6mo. Don't mix with a 20 grade.

Best of luck with that old girl.
 
Here the new version is a API SP A3/B4 Syn Blend, i assume Group 2/3.
But yeah, the data sheet and the description of the oil on the TDS is pretty lacking as expected from Castrol.

View attachment 265149
I have a 5L jug of that I bought 4 months ago. The pds shows A3/B4, but there’s no mention of it on the container, just api/sp and no mention of it being a synthetic blend.
On sale with stacked savings it worked out to about $20 USD.
If it’s truly a3/b4 I’ll use in my lawn tractors which both have the 726cc Kawasaki engine.
 
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