ARTICLE: Synthetic oil vs Mineral oil

[Sawyer]

Originally Posted by DieselFan

Mobil 1 is not an oil recommended for Diesels

Who says so? Mobil has no hesitation in recommending it for diesel engine use, btw. So from where does this contradiction arise?

[Jaggu]

Originally Posted by Sawyer

Who says so? Mobil has no hesitation in recommending it for diesel engine use, btw. So from where does this contradiction arise?

"Ideally" not recommended but no adverse effect if the grade is good enough.

For the umpteenth time let me quote Car Bibles : The Engine Oil Bible

Part 1- Underlined the relevant section

Can I use diesel engine oil in my petrol engine?

This is an awkward question to answer. Diesel engines run much higher compression ratios than petrol engines and they run a lot hotter, so the oil is formulated to deal with this. Plus they produce a lot more dirt in terms of combustion by-products. Diesel-rated oils typically have more detergents in them to deal with this (see Using Diesel oil for flushing above). It's not unheard of for diesel oils to clean a petrol engine so well that it loses compression. Diesel-rated oils also have an anti-foaming agent in them which is unique to diesel engines, and not needed in petrol engines.

So is that the be-all and end-all answer? Well not really and that's why this is a difficult question to give a straight answer to. The above statement is more relevant to commercial diesel engines. Nowadays, just about all passenger car / light commercial oils (including OEM ones designed for both petrol and diesel engines) will carry the ACEA A and B specifications. ie. formulated to satisfy the requirements for both types of engine. So just because the oil is labelled "Diesel" doesn't mean it's not suitable for petrol engines - it will more than likely carry an ACEA A3 / OEM petrol spec as well.

However you do need to be a bit careful regarding choosing the right diesel spec - if you have a modern common rail / direct injection diesel, chances are it will require at least an ACEA B4 spec to cope with the higher piston temperatures that can cause piston deposits (and stuck rings). ACEA B4 is fine where B3 is recommended.

[Sawyer]

This is what I do not understand. When Mobil recommends it, who is the "ideally"? And from what I have read on the site, Mobil 1 in both 0w40 and 5w50 meets all the specs referred above too. Given this, why they would have a separate diesel synth line is beyond me, when they merrily state that quote Mobil 1 0W-40 is recommended for all types of modern vehicles, especially high-performance turbo-charged, supercharged gasoline and diesel multi-valve fuel injected engines found in passenger cars, SUVs, light vans and trucks unquote.
So my question stands.

[nitrous]

Originally Posted by Sawyer

This is what I do not understand. When Mobil recommends it, who is the "ideally"? And from what I have read on the site, Mobil 1 in both 0w40 and 5w50 meets all the specs referred above too. Given this, why they would have a separate diesel synth line is beyond me, when they merrily state that quote Mobil 1 0W-40 is recommended for all types of modern vehicles, especially high-performance turbo-charged, supercharged gasoline and diesel multi-valve fuel injected engines found in passenger cars, SUVs, light vans and trucks unquote.
So my question stands.

So, Mobil's website is the gospel truth?

Go by technical specifications.

[Sawyer]

And pray where can I get Mobil tech specs on any site other than Mobil? On the other hand, do I believe "ideally", just because the word is used?!

[Jaggu]

Did you read the underlined part??!! Diesel engine oils have some added detergents and better soot control!! apart from heat range. This irrespective of Mobil or IOC!!

EDIT: check diesel oil packs these are explicitly mentioned, where as in petrol oils not much of emphasis given.

This DOES NOT mean that Mobil 1 will SCREW the engine up!! But also doesnt mean its the be all and end all when it comes to oils!! Even if Mobil wants to project that!!

Also they have a very good business everywhere else for Mobil Delvac 1 series of oil.

Its not a mystery why its not sold here in India, since diesel was and is majorly associated with all things cheap, starting from the fuel price. Only in recent past has higher end engines and owners have come into the picture. So be patient we will get our Delvac's in couple of years!!!

I really dont understand why so much of up and down argument, when these are universally studied and published technical info.

[Sawyer]

Originally Posted by Jaggu

I really dont understand why so much of up and down argument, when these are universally studied and published technical info.

Perhaps because some of us are not as smart as you?

[Jaggu]

LOL no way am smarter than any of us here with internet access. I did hell lot of reading up aided by google to find a suitable solution for Diesel swift oil. Thats when i came across these info.

Mainly discussed to death in forums, and there were some independent oil review sites which also mentioned in detail the effect of oil on engines. Anyways i wish we had better access to better oils, tires and after market mech's to make our life easy as a car enthusiast.

OWS has a nice synthetic brew for diesels, havent tried it though. Rippergeo should be able to help us with a review

cheers
Jaggu

[Sawyer]

Originally Posted by Gansan

A query related to this point. If the oil happens to be spurious despite all precautions, can it be found out during usage? I mean, will there be any odd symptoms like engine overheating etc., so that we can at least flush it from the engine immediately?

Since you mention precautions, I would include in that seeing the oil as it is poured into the sump. If it looks brand new as it pours, even if spurious, it will still work! If someone is switching oils and pouring used oil back in, it will be very visible too.
That said and addressed, I am not sure that symptoms will surface right away. Many of the immediate symptoms will arise from things such as poor quality fuel, coolant loss, choked air filter, timing issues, fouled plugs, and the like. One would usually address those first before turning to spurious oil. The ill effects of "good" spurious oil will be visible only in the longer term.
My recommendation if you are not in a metro, and are concerned about the oil, is to go to the MASS for your car - I cannot imagine that any of them would use spurious oils - but then, and no disrespect intended, I haven't got enough experience of non metro central/north/east India. As far as MASS are concerned, even if their Servo oils are not glamorous, changed every 6 months, they will still do a good job in the car. In Chennai, it would be hard to buy spurious oil from an accredited distributor, I think. But if really in doubt, stick to the city MASS. To be doubly sure, the sales and service outlets. In theory they can also use spurious, but then in theory, currency notes can be so too!
I hope this helps.

[Sawyer]

@Jaggu - now hear this!
I poured close to 8 litres of Mobil 1 in my Pajeros sump after doing a lot of research, and because no other synth was available. By the way, the manual says that anything better than CD is ok, it is an old generation engine after all. And among the alphabet soup in the Mobil 1 tech spec, was CF, which was why I decided to go ahead. Unfortunately, I kept doing more research, and discovered CF4....and CG4 and CH4. And never quite figured out how the numerics suddenly sprouted in the API C classifications, was too fed up by then. I then found that good old Castrol RX Super plus, in meeting CH4 spec is a pretty advanced formulation for diesels, and a great bargain to boot, even more so for 8 litres sumps.Given my preference for 6 monthly changes, regardless of kms run. Switched to it, and lost my synthetic infatuation for good too! And was pissed of too because that expensive Mobil 1 is still stuck at CF, while its S classification keeps progressing, now at SM I am guessing. It still meets all the ACEA benchmarks that you have underlined, but I thought enough is enough of this nonsense and switched to straightforward mineral blends.

[tsk1979]

Originally Posted by Sawyer

@Jaggu - now hear this!
I poured close to 8 litres of Mobil 1 in my Pajeros sump after doing a lot of research, and because no other synth was available. By the way, the manual says that anything better than CD is ok, it is an old generation engine after all. And among the alphabet soup in the Mobil 1 tech spec, was CF, which was why I decided to go ahead. Unfortunately, I kept doing more research, and discovered CF4....and CG4 and CH4. And never quite figured out how the numerics suddenly sprouted in the API C classifications, was too fed up by then. I then found that good old Castrol RX Super plus, in meeting CH4 spec is a pretty advanced formulation for diesels, and a great bargain to boot, even more so for 8 litres sumps.Given my preference for 6 monthly changes, regardless of kms run. Switched to it, and lost my synthetic infatuation for good too! And was pissed of too because that expensive Mobil 1 is still stuck at CF, while its S classification keeps progressing, now at SM I am guessing. It still meets all the ACEA benchmarks that you have underlined, but I thought enough is enough of this nonsense and switched to straightforward mineral blends.

Not Mobil 1s fault. Mobil makes API-CH4, and even API-CI4 oils, but they are not available in India, as its more popular among petrol heads.
In diesel land, I don't have any idea about a synthetic oil which is API-CH4 or higher, and readily available in India.
That said Castrol GTX diesel and Mobil Super 1000 are API-CH4, and great for your car.

[Jaggu]

@Sawyer: I think you did the right thing! a) since you change oil every 6 months b) since its an older design (engine) investing on very high end oil might not really make sense. Yes Castrol RX did have some good reviews and was a pretty good brew.

Things get complicated as the engine development advances and thats where i got stuck with available synthetics in Indian market. Especially with the oil sump (quantity of oil required for engine) becomes less, which will make it double the work for oil. FYI DDIS engine takes 3.1 liter oil with filter change, this is a diesel engine with EGR so obvious load on oil to keep things clean in there and then lubricate vital parts. Very honestly i believe that regular oil change can negate bad effects even if we are running slightly genuine low grade oil. Maybe a reason why MUL and Honda prefers good ol mineral and change at 5k kms, though their service intervals might be 10k kms.

EDIT: I wanted to add one lil point here, the above statement doesnt mean its OK for manufacturer's to stop a customer insisting on a better oil in their cars. Egs: I might want a synth like Mobil1 in the engine, since i might be doing crazy rev limiter driving occasionally and long highway trips, where that extra protection will come in handy. This might be just 10% of my drive during a normal oil change cycle. But it sure will help. Buffer factor is always good for people who are lil on careless side when it comes to scheduling services, i have one in my family lol and that car hasnt had an oil change for 14k kms while running on servo! EDIT END

Continued with old story: The old petrol zen ran on servo till about 20k kms but oil changed at 5k intervals sometimes even lesser kms. When the valve cover was inspected at 20k kms the inards were clean with just a mild discoloration. Then i shifted to GTX2 which was the fav from castrol those days, there was a very evident change in engine note (more sharp and crisp) and i felt it revved a lil bit smoother also. Added to this i started pushing the oil change to 7-8 k kms and could see that the newer brew survived without leaving any stain. Then Magnatec came and very honestly difference was minimal compared to GTX2 but defenitely better.

Finally switched to Mobil 1 (newly launched and just for the heck of it) at around 57k km mark, after using flushing oil. Difference was felt, as if the engine had regained life of about 30k kms, atleast from the feel of engine. This is an all aluminum engine from suzuki, so i guess a good oil helped.

But by around 10k kms of Mobil, oil color started changing (dark brown) and oil became thicker. Which actually is a good sign (me guess) since the oil seems to be doing what it should be, but a negative mark on extended drain interval, which Mobil marketing used to "claim".

I never bothered with better oils in the cars that came in between (Fiat 118NE, Maruti 1000, Gypsy with 1000 engine) and used to fill Magnatec till my iKON. The shift to Mobil 1 happened at 20k kms in iKON and it was superb. The 1.6 Rocam engine became super smooth and crisp, but here also i decided to go for a new fill at 8k kms since the same old color change happened with the oil.

So in short my inference is, unless the engine is high tech mumbo jumbo, putting a seriously high grade oil might not really be that useful. In some cases the thinner oil makes the engine noisy and rough. Secondly even if using premium synth's, changing oil frequently is recommended. Especially if the engine runs in stop and go traffic and short trips.

If you havent gone through the Engine oil bible link i posted earlier, you can go through it to get answers to naming convention (rather the chaos), even the castrol rebel activities is also mentioned there.

[Sawyer]

Originally Posted by Jaggu

Very honestly i believe that regular oil change can negate bad effects even if we are running slightly low grade oil. Maybe a reason why MUL and Honda prefers good ol mineral and change at 5k kms, though there service intervals might be 10k kms.

Secondly even if using premium synth's, changing oil frequently is recommended. Especially if the engine runs in stop and go traffic and short trips.

I fully agree, and you, my dear Sir, have taken the baton over fully, based on what you have said above. I shall now go and on some other subject elsewhere on the forum! I would just add the word genuine after the low grade adjective above.

[Jaggu]

Originally Posted by Sawyer

I fully agree, and you, my dear Sir, have taken the baton over fully, based on what you have said above. I shall now go and on some other subject elsewhere on the forum! I would just add the word genuine after the low grade adjective above.

Dear sir,

you aint getting off this thread so fast! I have some research pending (dont we all) and your inputs would always help bring things on track.

cheers
Jaggu

[DocG]

Originally Posted by sgiitk

US Honda has 3000 mile oil change

US is worse. It is 3000 miles !! Here is an excerpt from the Honda Service Schedules:

Minor Service Interval
Mileage: 3,000 - 6,000 - 18,000 - 21,000 - etc.

That's absolutely correct. World over Honda comes from the factory with 5W20 mineral oil. Hence the oil changes come up fast. But then again in the US owners insist on synthetic from their first change onwards. This takes their change intervals to around 7.5K to 10K Miles.

Originally Posted by Sawyer

All I can say is that Honda is being consistent, that translates to 5000kms, give or take. I can't see too many Americans in compliance, but will defer to any actual user comment.

Americans have their oil changed every 3-4 months. If you get it done from the dealer it costs somewhere around 20-30 US for an oil change. But when you DIY which many do, the oil costs are somewhere around 10 bucks. The filter around 6/7 dollars.

**FYI I just changed the oil in my Accord, thank god it's out of warranty.

I used a K&N Gold oil filter and 5L of Petronas 5W40 synthetic. The total cost incurred for all items and labour was Rs 4100. The engine ate up all 5L. Plan to change in 10K KM.**