ARTICLE: Synthetic oil vs Mineral oil

[Vivek5870]

Originally Posted by sgiitk

I do not see how the engine knows what oil is put in. Al long as the viscosity is fine, no damage done. Why is simple, around 1998 or so Synth was not easily available, and I saw no advantage in paying Rs.1400 for a canister. So it was back to GTX.

Sir, can you let me know the oil that you are using currently in your civic and what brand of engine oil do you recommend for a OHC (irrespective of the xWxx). I have used Castrol GTX Magnatec in my last service and post 2000 kms, I find a little roughness in the engine performance. I have used same oil earlier also in Maruti 800 and have got excellent performance.

Anything that you recommend that I should be adding to this oil for improved performance?

[Gansan]

I buy the HX 5 in 3 litre pack nowadays. No need to measure out the oil. I use the full pack during the oil + filter change, ensuring complete drain of the old oil. Settles at slightly above the upper mark on the dip stick, which is pretty much ok. The level remains almost the same till the next oil change.

[Vivek5870]

Originally Posted by Gansan

I buy the HX 5 in 3 litre pack nowadays. No need to measure out the oil. I use the full pack during the oil + filter change, ensuring complete drain of the old oil. Settles at slightly above the upper mark on the dip stick, which is pretty much ok. The level remains almost the same till the next oil change.

Gansan, do you recommend the HX5 5W40 for OHC? Will this be a VFM choice along with optimum performance. I am currently using Castrol GTX Magnatec in my OHC and find the running a bit rough. Is it a ok if I just downgrade from semi synth to a mineral without a flush? Will it do any harm to the engine if I dont flush out the synth content without a flush and quench the thirst of my ride with HX5 mineral?

[Gansan]

Originally Posted by Vivek5870

Gansan, do you recommend the HX5 5W40 for OHC? Will this be a VFM choice along with optimum performance.

If 15W40, API SL is acceptable according to your owners' manual, this oil will be fine. No need to apply engine flush, it is perfectly OK to switch between mineral to synth and back again. Just ensure as much of the old oil as possile is drained during the oil change.

As a thumb rule if your recommended oil is xxW/yy and API SH (example), the lower figure of the oil you select should be equal to or less than xx; and higher figure should be equal to or higher than yy. The API rating should be SH or higher. It is immaterial whether the oil is synthetic or mineral (by default certain grades will only be semi-synth or fully synth). In my opinion, Shell is more preferable than Castrol, for the simple reason fakes are unlikely in the former!

It is generally preferable to go higher than yy if the car has done at least 50,000 KM; else stick to yy.

And don't worry too much about the brand! Any reputed brand bought from a reliable source will be fine!

[R2D2]

Originally Posted by Vivek5870

Gansan, do you recommend the HX5 5W40 for OHC? Will this be a VFM choice along with optimum performance. I am currently using Castrol GTX Magnatec in my OHC and find the running a bit rough. Is it a ok if I just downgrade from semi synth to a mineral without a flush? Will it do any harm to the engine if I dont flush out the synth content without a flush and quench the thirst of my ride with HX5 mineral?

The OHC Type I & Type II used 20W-50 as default viscosity. Try to stick with the recommended grade. The only oil I used in my OHC was Mobil 1 5w-50 (just once) and 20W-50 provided by the ASC. Castrol Magnatec 10W-40 is too thin for this engine. You can also consider Shell Helix HX3 which is 20w-50.

Using Mobil 1 will make a big difference to your engine, the only issue is the drain interval of 5K kms which doesn't make it worth the money. You could stretch Mobil 1 to a max of 7500 kms before an oil change.

And please, please, please do NOT use an engine flush even if you shift to synthetic from mineral or vice versa.

[Sankar]

Originally Posted by blackfire_9

most of them (at least the ones commonly available in India) are simply highly refined petroleum base stocks & not "true" synthetics.

Mobil 1 is a Group4 synthetic which is a true Synthetic.

Mobil Super 3000, Shell Helix Ultra and Castrol Edge, Total Quartz 9000 are Group3 synthetics as far as i know which are mineral base hydro cracked.

So in my knowledge the only group 4 synthetic oil available in the country is Mobil 1 (i wish the 0W30 grade was sold locally).

Does Motul markets automobile oils here? They had group 4 motorcycle synthetics on sale here.

Edit: If the oil is specified is Synthetic in Germany its a group 4. In US group 3 can also be marketed as Synthetic. Mobil and Castrol warred over this some years ago, Mobil was not happy to see Castrol group 3 being marketed as Synthetics in USA at a cheaper price than Mobil 1.

TechBrief10 - Oil Base Stocks.pdf

[Vivek5870]

Originally Posted by R2D2

The OHC Type I & Type II used 20W-50 as default viscosity. Try to stick with the recommended grade. The only oil I used in my OHC was Mobil 1 5w-50 (just once) and 20W-50 provided by the ASC. Castrol Magnatec 10W-40 is too thin for this engine. You can also consider Shell Helix HX3 which is 20w-50.

Using Mobil 1 will make a big difference to your engine, the only issue is the drain interval of 5K kms which doesn't make it worth the money. You could stretch Mobil 1 to a max of 7500 kms before an oil change.

And please, please, please do NOT use an engine flush even if you shift to synthetic from mineral or vice versa.

Thanks Gansan and R2D2 for the response. Will keep this in mind during the next oil change.

[blackfire_9]

Hey raccoon, please find my comments inline.

Originally Posted by Raccoon

If 10k, 1 year drain interval is recommended, one can be pretty sure the manufacturer has taken care to make sure the additives last for that long. If the car sees more bumper to bumber city driving, then it may be worthwhile to change the oil a couple thousand km earlier or so, depending on the magnitude of such driving. A 6 monthly change (double) seems like an overkill.

I agree that it's a safe bet to stick with the manufacturer specified intervals & what I had said earlier was simply my thought/opinion on what is appropriate. The basis of my opinion was the UOA reports that I have read on the Internet from time to time, which make me believe that the ideal life-span of an additive is close to 6 months once inside an operating environment (i.e. an engine). And please note (kindly refer to my posts again), my opinion is limited to the duration between oil changes & not the mileage between them, which is to say that if a manufacturer recommends 10K between oil changes, I would believe it's alright.

Secondly, a lot of car manufacturers have revised the service intervals on their cars just to give the impression of a low cost of ownership/servicing to a prospective customer. For example, look at Ford 1.4 TDCi engines or the Maruti DDiS twins, where the first oil change is now at 10K kms, something much higher than what used to be till some time back. And these engines have neither really undergone any technical change, nor has the quality of oil being used changed to warrant such intervals all of a sudden. That's why, I feel that despite whatever the manufacturer or anybody says, one should use their discretion as well.

Also, let me point out more concern - unless you have the means to exercise total control over the oil changing process, its more than likely that contaminants will get into the engine during the process. Our mechanics and service center are fairly shoddy. Chances are that damage caused by these contaminants is more than the benefits (if any) of changing the oil sooner than recommended.

I am sorry but from your paragraph above, I couldn't really draw much relevance to this discussion.

However, I would just say that timely oil changes (manufacturer prescribed or earlier) would prevent or reduce the buildup of such contaminants that may damage an engine.

Secondly, changing engine oil is no rocket science & the bare minimum precautions have to be taken irrespective of whether an oil change is done according to manufacturer's recommendations or otherwise. In this discussion between synthetics & minerals, its a given (more like a control) that the mechanics or SCs carrying an oil change have the basic competence.

Lastly, if "our" mechanics & SCs are shoddy, then changing oil even at manufacturer prescribed intervals looks risky to me & I hope you are not hinting at continuing to run an engine with the same oil throughout the life-span of it.

As for comparing with Taxis, contrary to popular belief, the operating environment of a Taxi can actually be way less taxing than an average single owner/family owned car. That is because a Taxi is usually always on the run whereas other avg. pvt. cars are used intermittently and hence suffer way more damage as they are cold started most of the times. Taxis will mostly always be operating at near optimum operating temperatures most of the times and other pvt. cars wont (so more sludge, carbon, etc). So chances are the average taxi may get away with lower quality lubing but the avg. pvt. car wont. Also, do we have any data about engine rebuilds, of taxis and single owner cars that we can compare with? And I'm not sure you can say taxis run "like a charm"... at least I'v not found it to be so in some/many cases I'v cared to notice.

Don't you think that because a taxi is usually on the run, even it experiences stress & damage (in the form of wear & tear)? The conditions are different but both the conditions present an engine with stresses & damage. If a private vehicle experiences these at the hands of cold-starts, a taxi experiences similar stresses out of continuous operation.

As for the engine rebuild statistics, no, I do not have any data pertaining to engine rebuilds for taxis & single-owner cars. And frankly, is that sort of an information even required here? I am not sure how it could help here when we are talking about the relative benefits of synthetic & mineral engine oils. Please understand that the reference to a taxi was only given to stress that the mineral oils are good enough.

As for running like a "charm", all I can say is that maybe the selection of the word was not quite appropriate here. But I stick to the fact that even a basic mineral oil is good enough for an engine to last many kms, the count of which may run into lacs.

Originally Posted by Sankar

Mobil 1 is a Group4 synthetic which is a true Synthetic.

Does Motul markets automobile oils here? They had group 4 motorcycle synthetics on sale here.

Edit: If the oil is specified is Synthetic in Germany its a group 4. In US group 3 can also be marketed as Synthetic. Mobil and Castrol warred over this some years ago, Mobil was not happy to see Castrol group 3 being marketed as Synthetics in USA at a cheaper price than Mobil 1.

Hey sankar,

I agree with you on the differences in the definition of synthetics across Germany & US. In fact, you rightly pointed out the legal battle that had ensued between the two oil giants, Castrol & Exxon Mobil. However, as far as I remember, it was only after Castrol had won this lawsuit, did Mobil change the configuration of Mobil 1 from Group-IV base stocks to Group-III. I think the MSDs of Mobil 1 also mention that the base stock is primarily of a petroleum type instead of PAOs; need to check again probably.

As for Motul, yes, they do market their products in India through a distributor in Mumbai. However, they are more expensive than their counterparts from other brands, as per my observation. Their synthetics though are still Group-IV or even V.

[Raccoon]

^^^I am not sure if you have seen them change oil in various garages. Either you have not, or you have been real lucky to see only ones where its done right. The shabby manner in which it is done ensures that you WILL get quite a bit of contaminants like dust and the link along with new oil. I'm sure this does not require further elaboration. I suggest people check it out themselves.

Changing oil involves no rocket science, but how many jobs do we see everyday that are not rocket science either, but are still not done well? How about my recent experience with jump starting by Exide's Bat Moble (details in another thread) as an example? Is jump starting a car rocket science? Yet you can count on people to make a mess of it. Anyway, if someone chooses to be oblivious of all these glaring acts of what I can only call vandalism, then there is nothing more to be said.

And yes, the oil in an average taxi does experience a less stressful environment, as compared to an average pvt. car, as mentioned. And now because I say so, but it has been found to be so. Don't the reasons already stated sound plausible enough?

[Sankar]

Originally Posted by blackfire_9

However, as far as I remember, it was only after Castrol had won this lawsuit, did Mobil change the configuration of Mobil 1 from Group-IV base stocks to Group-III. I think the MSDs of Mobil 1 also mention that the base stock is primarily of a petroleum type instead of PAOs; need to check again probably.

Castrol won and group 3 can be called synthetic, but only in USA. If Mobil 1 markets their oil as synthetic in Germany then these are true synthetics.

Mobil 1 Products

Mobil 1, complete range = Chemical synthesis
Mobil Super 3000 = Synthetic Technology. This matches with the info i had about this oil that its Group 3 hydrocracked.
Mobil Super 2000 = Part synthetic. Don't think its sold here.
Mobil Super 1000 = Mineral oil.

Some screenshots of Mobil 1 oils in random from their JP site, has all Super series oils too.

[R2D2]

Originally Posted by Raccoon

^^^I am not sure if you have seen them change oil in various garages. Either you have not, or you have been real lucky to see only ones where its done right. The shabby manner in which it is done ensures that you WILL get quite a bit of contaminants like dust and the link along with new oil. I'm sure this does not require further elaboration. I suggest people check it out themselves.?

+1

Oil changes are more often than not done quite shabbily, for e.g. without cleaning the engine oil cap or the funnel they use to pour oil. The filter gasket is coated with used engine oil instead of fresh oil. Quantity of oil being poured in is not measured properly - they pour according to their 'expert judgement' and use the dipstick to check the level AFTER it is in the engine. If there's excess - 'no problem saar! topup karna nahin padega' the same theory goes for battery distilled water.

That's why I keep a very close eye on what the tech is doing with my car.

I have seen engine heads being taken off and the block not covered with a plastic sheet to prevent dust from going into the cylinders. It is the classic chalta hai attitude. I don't say everyone does it - but it does merit closer inspection to check how the mechanic is treating your car.

[blackfire_9]

I am sorry for your experiences ( of simple things going wrong) with your vehicles, but they are yours & not a general truth or fact. I agree that simple things or tasks can also cause harm if not carried out methodically & carefully, but it is not always so as in your case. I have not overlooked these possibilities that you have mentioned & I am sure most do not, rather I have chosen to be cautious & ensure that by keeping my senses open & not leaving the task entirely onto the mechanic (trusting blindly), I keep these possibilities at bay especially in case of such simple tasks (like I have till now, by God's grace). Moreover, I think I know of a few decent places to carry out these tasks (any simple tasks including & not limited to oil changes) without any "glaring" mistakes & so do quite a number of BHPians since we do have that TBHP directory & recommendations made throughout the thread.
Possibilities of something going wrong are always there in anything, but it's up to us to try & curb them instead of not getting the task done at all. Something that our fellow BHPian has said above, "keep a close eye on the tech".

Maybe you need to extend your car's oil drain intervals to the limits then, since you may just damage something in there & I say this out of your own experience (as quoted in your post below).

Lastly, about the taxi & now that you mention it, could you please share the research data on the stresses faced by a taxi & a private car since as per your words, it has been "found" that a taxi has a less stressful environment.
Honestly, I thought this was a debatable topic wherein one couldn't pin-point the extent of stresses on either category of cars as the results would always be ambiguous; rather it could be assumed (as I have written earlier) that both categories of vehicles experience different conditions but similar levels of stress. So, would love to see some data on it & no, the explanations are not enough to quantify the stress levels of a taxi as being more than that of a private car.

Originally Posted by Raccoon

^^^I am not sure if you have seen them change oil in various garages. Either you have not, or you have been real lucky to see only ones where its done right. The shabby manner in which it is done ensures that you WILL get quite a bit of contaminants like dust and the link along with new oil. I'm sure this does not require further elaboration. I suggest people check it out themselves.

Changing oil involves no rocket science, but how many jobs do we see everyday that are not rocket science either, but are still not done well? How about my recent experience with jump starting by Exide's Bat Moble (details in another thread) as an example? Is jump starting a car rocket science? Yet you can count on people to make a mess of it. Anyway, if someone chooses to be oblivious of all these glaring acts of what I can only call vandalism, then there is nothing more to be said.

And yes, the oil in an average taxi does experience a less stressful environment, as compared to an average pvt. car, as mentioned. And now because I say so, but it has been found to be so. Don't the reasons already stated sound plausible enough?

[Gansan]

I take the engine oil and a funnel to the workshop; oversee the draining process, tell them to remove the filter even as the oil is draining and remove the oil filler cap myself (and clean it) to aid faster draining of the oil.

I make them wait for as long as possible for the old oil to drain out. They coat the new filter's rim with a little of the used oil, but I overlook it since I change the oil at around 5K Km mark. Only after the drain plug and filter are installed, will I open my 3 litre can of fresh oil and make them pour all of it inside with my own funnel. Then for checking the level with dip stick, I provide some facial tissue rather than let them use some dirty waste!

[Raccoon]

Originally Posted by R2D2

+1

Oil changes are more often than not done quite shabbily, for e.g. without cleaning the engine oil cap or the funnel they use to pour oil. The filter gasket is coated with used engine oil instead of fresh oil. Quantity of oil being poured in is not measured properly - they pour according to their 'expert judgement' and use the dipstick to check the level AFTER it is in the engine. If there's excess - 'no problem saar! topup karna nahin padega' the same theory goes for battery distilled water.

That's why I keep a very close eye on what the tech is doing with my car.

I have seen engine heads being taken off and the block not covered with a plastic sheet to prevent dust from going into the cylinders. It is the classic chalta hai attitude. I don't say everyone does it - but it does merit closer inspection to check how the mechanic is treating your car.

After experiencing all "expert professional care", what I'v learnt is that less your vehicle is touched by all these "expert hands", the better it is for its health. A lot of overzealous and well meaning owners (including me in some ways, in the initial years) do more damage than good. Needless/premature oil changes probably tops the list.

Originally Posted by blackfire_9

[b]
Maybe you need to extend your car's oil drain intervals to the limits then, since you may just damage something in there & I say this out of your own experience (as quoted in your post below).

Lastly, about the taxi & now that you mention it, could you please share the research data on the stresses faced by a taxi & a private car since as per your words, it has been "found" that a taxi has a less stressful environment.
Honestly, I thought this was a debatable topic wherein one couldn't pin-point the extent of stresses on either category of cars as the results would always be ambiguous; rather it could be assumed (as I have written earlier) that both categories of vehicles experience different conditions but similar levels of stress. So, would love to see some data on it & no, the explanations are not enough to quantify the stress levels of a taxi as being more than that of a private car.

I'm afraid you have completely missed the point. Lets not agree on anything, but lets agree on not debating this further. I feel there is sufficient material already mentioned and hinted at for others concerned to form their own conclusion.

About the taxis, it isn't my pet theory - I had learnt the same from a reliable source in the past. Unfortunately, I am unable to recall the source right now. If I recall, I will try and mention it later. Meanwhile, or even if I don't, I imagine people can form their own opinion with the points already mentioned, if they are aware of the basics of lube science (cold starts, sludge, blow by and the like).

[NMM]

I feel synthetic oil is best for car engines. Especially if its a car you want to keep for long. I use synthetic oil only in my good old steed - my Lancer 2001 glxi, its done 137,000 + kms. Since i moved to synthetic oil the car runs noticeably smoother ( maybe even slightly quicker ). If your car is decently maintained, ideally when you move to synthetic also try & add a k&n filter. Its the best/easiest thing you can do to prolong engine life, add power & increase efficiency.