[FlatOut]

Originally Posted by Sawyer

The grade move needs a change in the base oil, not just in the subsequent additive package or manufacturing technology.
Consider this: it is more expensive to keep two API grades in the line up than it is to standardise on one grade, even if that is the more advanced one. But, in transition and unless others have done so too, there is the marketing opportunity to extract a higher price for the better oil, so how do you do this? The market at large doesn't understand the alphanumeric jumble of letters as a differentiator, but "synthetic technology" as a blurb is noticed even in rural markets not fully conversant with English. But it doesn't mean a thing in itself.
Semi-synth is even cleverer. A long time ago, a liquor industry insider told me that if he added a peg of Scotch to a barrel - or more - of Indian whisky, he was legally entitled to call it " Blended with Scotch", and sell it at a higher price for that attribute. I am sure you can see the analogy!
Pure synthetic is a different story, but a same API grade mineral is just as good for normal road use cars.

That is very well put!

People seem to become fixated on whether oil is mineral or semi-synthetic, whereas perhaps they should be judging the quality of the oil somehow, maybe there are some test results on the net? Also, make sure the oil is right for the engine, it's amazing how many people run the wrong grade.

I can feel when an oil is losing its properties in some engines, they become a little noisier and rougher. Many years ago I carried out my own tests and found Total 15W40 was the best performing oil for my applications, by quite a margin. If you are aware when oil starts to lose some of its lubricating properties, then perhaps you should run a test with four or five different oil brands and decide on which you feel the engine ran best, for longest.

Recently the price of my Total oil went through the roof and I only use this where I feel it is strictly necessary, since I bought 205 litres of cheaper 15W40 for a very good price indeed - about 40% of the price of Total's. I'm not as hard on engines as I was ten years ago but change the oil at about 75% through the period to which I would run the higher quality oil.

A friend running an old engine with a little wear in the bottom end sought the advice of an oil supplier who specialises in oil for old and vintage cars. The engine promptly broke on a long, fast run - something it had regularly been doing before but on what I considered the best oil for it.

My friend listens a little more carefully to my advice now and uses the correct grade modern oil. The only advantage of oil specially designed for old engines is that it may not have detergent as an additive, so that decades-old sludge in the sump and galleries is not dislodged with potentially serious consequences.

[Sawyer]

Originally Posted by Gansan

No, thanks!

All Maruti A.S.S.places are now using only semi synthetic 5W30 MGO for all cars, whereas that is recommended only for the K10 engines. Previous engines needed 20W40.

Compared to that, the 10W40 HX 7 is much better, so I will keep it!

The 5W30 may actually be the better oil, the more the difference between the two numbers, 25 in the case of the MGO compared to 30 for the HX7, the greater the challenge for the oil to remain effective over the entire duration of its use. In practice there isn't much of a difference between the two.
The reason why they are using the 5W30 across all cars is because it is simpler, and therefore on an overall cost basis lower, to standardise.

Originally Posted by FlatOut

perhaps they should be judging the quality of the oil somehow, maybe there are some test results on the net?

That's the thing that would be useful. Between 2 equally known brands, with oil of the same spec, how does one know which is the better one for the run of the mill modern car?

[Gansan]

I went back to the packs of HX7 (cars) and the AX 7 (Motor bikes) and found while the label in the former proclaims "Synthetic Technology Motor Oil", that of the latter says "Semi-synthetic Motorcycle oil". While both are 10W40, the car oil is API SM, while the bike oil is API SL.

Now why is that? I thought both were same, minus some friction modifiers for the bike oil.

[Sawyer]

Originally Posted by Gansan

Now why is that?

Your guess is as good as mine - maybe they had stock of older bottles/labels they wanted to use up?

[Sawyer]

Originally Posted by FlatOut

I can feel when an oil is losing its properties in some engines, they become a little noisier and rougher.

Among a few others, that is the reason why a car feels a smoother drive after a service/oil change. Expectation bias leads to the belief that the change to synthetic, more expensive oil is the cause. AFAIK, no one has done a scientific double blind test to establish that this smooth feeling is really attributable to a change in the nature of oil used for the oil change. People want to believe what they are led to expect to see happen, and clever marketers prey on this susceptibility to extract more money from them.

It happens everywhere - high end audio is a classic example. Giving a baby who is blessed to have a healthy breast feeding mother, vitamin/mineral supplements as an "additive package" is another. Marketers every where are masters of human psychology and vulnerabilities.

[sagarpadaki]

Originally Posted by Sawyer

Among a few others, that is the reason why a car feels a smoother drive after a service/oil change. Expectation bias leads to the belief that the change to synthetic, more expensive oil is the cause. AFAIK, no one has done a scientific double blind test to establish that this smooth feeling is really attributable to a change in the nature of oil used for the oil change. People want to believe what they are led to expect to see happen, and clever marketers prey on this susceptibility to extract more money from them.

It happens everywhere - high end audio is a classic example. Giving a baby who is blessed to have a healthy breast feeding mother, vitamin/mineral supplements as an "additive package" is another. Marketers every where are masters of human psychology and vulnerabilities.

I disagree . Synthetic oils retain smoothness for much longer than minerals. Case in point being

1. When i changed from Delvac MX(mineral) to Delvac 1(Fully synthetic) the smoothness was present till the oil was 10,000 kms old. Beyond that the smoothness started reducing. Whereas with Delvac MX the smoothness was gone @ 4,000 odd mark


2. On my pulsar, a semi-synthetic Valvoline 20W50 smoothness lasts 1,500. There is an abrupt switch from smooth -> rough at this mark which has amazed me since i have not seen this behavior in any other oil. Whereas the fully synthetic Motul 300V was going great guns even @ 6000 kms.

[audioholic]

Originally Posted by Sawyer

All talk about smoothness on using expensive fully synthetic oil is either expectation bias founded or the outcome of a proper service of any car which is when the oil changes are usually carried out.

Though cars do feel smooth after a routine maintenance, I dont think that will make the effect of synthetic oil on engine behaviour go unnoticed. I changed my Dio's oil to full synthetic oil, after running previously for just 1k km on Shell AX7 Semi synthetic oil. This was just an oil change and not a routine service. Though immediately I did not find much difference, after around 100 kms of riding, the difference was and is very much noticeable in terms of smoothness of the engine as well as its ability to accelarate suddenly. This I am speaking in comparison with two other Dios that are owned by a relative and another by my friend. Even after a service, I did ride those scooters and whereas engine vibrations were present, only driveline vibrations were smoothened out due to the effect of the service. The engine felt coarse and vibrated a lot on revving.

[FlatOut]

Originally Posted by sagarpadaki

I disagree . Synthetic oils retain smoothness for much longer than minerals. Case in point being

1. When i changed from Delvac MX(mineral) to Delvac 1(Fully synthetic) the smoothness was present till the oil was 10,000 kms old. Beyond that the smoothness started reducing. Whereas with Delvac MX the smoothness was gone @ 4,000 odd mark


2. On my pulsar, a semi-synthetic Valvoline 20W50 smoothness lasts 1,500. There is an abrupt switch from smooth -> rough at this mark which has amazed me since i have not seen this behavior in any other oil. Whereas the fully synthetic Motul 300V was going great guns even @ 6000 kms.

I am not saying synthetic oils are no better - quite the opposite if you read back through my posts. With the proviso that your engine mustn't contaminate the oil with unburnt fuel, since no matter how good an oil, this contamonation ruins its properties. Tiny carbon particles are sharp and hard and when this happens (usually by 10,000km) any oil needs to be changed, no matter how well it retains its own properties.

So a very clean-running high-performance engine, or one which is running up to and beyond its design envelope will benefit from fully synthetic. Which is really very few indeed.

The point I (and others) have been trying to get over is that semi-synthetics are often a way of extracting more profit. A good quality mineral oil of the correct grade is what i recommend in 90% of engines, combined with regular changes. In Europe, goods vehicles have large oil sumps filled with expensive oil, a sample of this is taken at regular intervals and tested - when the oil is deteriorating and/or contaminated, it is replaced.

[Sawyer]

Originally Posted by FlatOut

So a very clean-running high-performance engine, or one which is running up to and beyond its design envelope will benefit from fully synthetic. Which is really very few indeed.

In Europe, goods vehicles have large oil sumps filled with expensive oil, a sample of this is taken at regular intervals and tested - when the oil is deteriorating and/or contaminated, it is replaced.

I agree. And the kind of testing you refer to is the way to extract the economic benefit, but it isn't something an individual car owner can do.

In ordinary road use, pure synths may justify their high premium, if they allow the drain period to be proportionately extended. It also would be eco friendlier, assuming that manufacture of synthetic oil consumes the same resources as a manufacturing a mineral oil.

But no car owner would want to take the risk of extending the recommended drain periods in that manner, particularly since no manufacturer endorses such extensions to the extent that engine warranties remain in force. Doing so would open a Pandora's box of possibilities and consequences, so the manufacturer stance can be understood.

[Sawyer]

Originally Posted by audioholic

the difference was and is very much noticeable in terms of smoothness of the engine as well as its ability to accelarate suddenly. This I am speaking in comparison with two other Dios

I hear you.

Please note however that the only way to make the scientific comparison needed to validate such a result is a double blind test, where nothing changes except the one single variable being examined. This has been known in laboratories for a very long time.

Admittedly these are hard to set up. For instance, here the vehicle should be the same, as should the road conditions be. Same fuel. Same time of the day. Except the oil in question, no other changes. And neither the rider, nor anyone associated in the testing, knowing which of the two variables are being deployed. And comparisons between alternate variables done often enough for the result to satisfy statistical rules. Perhaps the only workable way to do this is to use two brand new vehicles, with different oils in each, and do the testing.

So, in practice, what abounds in every such comparison - and not just engine oils or the auto industry - are subjective declarations that aren't scientifically valid.

Marketers know this, and human psychology very well, and exploit this to the hilt for additional profit.

[sagarpadaki]

Originally Posted by FlatOut

I am not saying synthetic oils are no better - quite the opposite if you read back through my posts. With the proviso that your engine mustn't contaminate the oil with unburnt fuel, since no matter how good an oil, this contamonation ruins its properties. Tiny carbon particles are sharp and hard and when this happens (usually by 10,000km) any oil needs to be changed, no matter how well it retains its own properties.

So a very clean-running high-performance engine, or one which is running up to and beyond its design envelope will benefit from fully synthetic. Which is really very few indeed.

The point I (and others) have been trying to get over is that semi-synthetics are often a way of extracting more profit. A good quality mineral oil of the correct grade is what i recommend in 90% of engines, combined with regular changes. In Europe, goods vehicles have large oil sumps filled with expensive oil, a sample of this is taken at regular intervals and tested - when the oil is deteriorating and/or contaminated, it is replaced.

Assuming the engine is a clean running one, a GOOD synthetic will out last mineral in both protection,longivity and smoothness. Whether the 2X~3X price difference between is justifiable or not is a personal perspective.

I completely agree with you on the semi synthetic ones.

[rahul4640]

A question gentlemen, please excuse me if it had been answered before.

I am a regular user of Mobile1 (0W-40) for last forty thousand in my car (MPFI, done nearly a lakh KM). I have also used Castrol edge once (0w-40) for slightly over ten thousand KM and found it to be an equally excellent oil.

But with my last oil change a month ago (Mobile1) I have come to see that the oil is slightly overfilled. The dipstick shows a raise of about 2 mm over the maximum mark. May it affect the oil seals? In that case how much oil should I drain and how do I measure it? Will not I get some impurity in my engine oil if I drain it fully and pour it again?

[Sawyer]

Originally Posted by rahul4640

But with my last oil change a month ago (Mobile1) I have come to see that the oil is slightly overfilled. The dipstick shows a raise of about 2 mm over the maximum mark. May it affect the oil seals? In that case how much oil should I drain and how do I measure it? Will not I get some impurity in my engine oil if I drain it fully and pour it again?

This is a typical Indian thing - we seem to love to add a little extra for luck! I wish they did this with fuel...
Overfilling above the max line isn't good, but it is hard to say about the 2 mm, because the tolerance for overfill will vary from engine to engine.
The safe thing to do is to drain out about 250ml into a clean vessel and recheck the level. If you find it to be between half and full, you can just leave things as they are. If it is close to halfway, add back half of what you removed.
There is no need to drain fully.

[Gansan]

Originally Posted by rahul4640

May it affect the oil seals? In that case how much oil should I drain and how do I measure it? Will not I get some impurity in my engine oil if I drain it fully and pour it again?

Which car is this? Maruti, I presume.

My MASS (MSM) fill three litres of oil in my Alto when they change the oil and filter. This shows a slight over fill the next day by an mm or two. They say it is OK, and I have never bothered about it. I suppose some tolerance will be built in to the design.

If you wish to remove some oil, don't drain it out. It is best to insert a thin, clean plastic tube through the dipstick opening and suck some of the oil out. Someone had posted a picture of such a pump he had purchased for this purpose from a medical shop, you can find it by searching back some pages. I think I saw it within the last two or three months.

[Sawyer]

Originally Posted by Gansan

My MASS (MSM) fill three litres of oil in my Alto when they change the oil and filter. This shows a slight over fill the next day by an mm or two. They say it is OK, and I have never bothered about it. I suppose some tolerance will be built in to the design.

Someone had posted a picture of such a pump he had purchased for this purpose from a medical shop, you can find it by searching back some pages. I think I saw it within the last two or three months.

The overfill in this case happens because a) they don't open the sump nut after running the engine so that the oil gets warm and drains freely and b) because they aren't willing to wait long enough for the last drop to fall. One could be obsessive about this, if one had the time and energy...

The said pump - very neat idea. I had one for my Bullet which is very sensitive to overfilling and will start leaking oil visibly if it gets too much oil.