[sgiitk]

Semi-synth can be a real can of worms. I will say a story to illustrate it:

A man was caught mixing horse-meat with chicken. So he was arrested and hauled up before the local beak.

Judge: Do you plead guilty.
A; Yes, my lord.
J: How much horse-meat were you mixing.
A 50:50
J: Please elaborate
A: One horse to one chicken.

So even 5% synth may qualify as semi-synth!

[vnabhi]

I have a question for car gurus: I have, on the advice of my S.A, used Mobil 1 5W 50 synthetic oil for the first time on my Fiesta when it was serviced last September. The engine refinement has gone up by several notches after that.

But as my usage is low (I generally cover 5000 to 6000 kms annually), should I replace the engine oil again this September? Or should I do it in the next service cycle which will be next year? I was told synthetic oils hold on till 10000 kms.

My other question is whether the car will have any issues if I switch back to semi-synthetic?

[DriveHigh]

Originally Posted by vnabhi

I have a question for car gurus: I have, on the advice of my S.A, used Mobil 1 5W 50 synthetic oil for the first time on my Fiesta when it was serviced last September. The engine refinement has gone up by several notches after that.

But as my usage is low (I generally cover 5000 to 6000 kms annually), should I replace the engine oil again this September? Or should I do it in the next service cycle which will be next year? I was told synthetic oils hold on till 10000 kms.

My other question is whether the car will have any issues if I switch back to semi-synthetic?

Hi vnabhi, Normally user manual recommends to change engine oil once in a year or 10000 Kms whichever comes earlier.
My father has 2006 Maruti Alto which he drives nearly 1000 Kms a year for last few years. Two years back I decided to put Magnatec 5W30 API SN (recommended is 20W40) and recently when I checked the oil using dipstick the oil still looks in good condition as I saw relatively less dust particle and the color was not too dark. I took it to our private mechanic who also said it is in good condition. Magnatec is semi synthetic oil and its popular in India. I hope as you do not drive much the Mobil1 5W50 tends to last longer. Synthetic engine oils are designed to provide superior protection in stressful driving condition specially for racing applications. However I would recommend you to perform periodical dipstick check to verify its quality. Chemicals tend to degrade over time depending upon the environmental exposures and probably this is the reason most of the manufacturers recommend one year change interval.

[sgiitk]

Originally Posted by vnabhi

I have a question for car gurus: I have, on the advice of my S.A, used Mobil 1 5W 50 synthetic oil for the first time on my Fiesta when it was serviced last September. The engine refinement has gone up by several notches after that.

But as my usage is low (I generally cover 5000 to 6000 kms annually), should I replace the engine oil again this September? Or should I do it in the next service cycle which will be next year? I was told synthetic oils hold on till 10000 kms.

My other question is whether the car will have any issues if I switch back to semi-synthetic?

I am not a guru but here are my comments:

1. Oil change in my view should be every 12,000km and/or 12 months whichever is earlier. I will say you can stretch the 12 to maybe 15 but not beyond. So 24 months will be a no-no.

2. No issues with returning to a semi- or even a mineral. I switched from Synth to mineral / semi many times with my old Esteem.

[DriveHigh]

Originally Posted by sgiitk

Semi-synth can be a real can of worms. I will say a story to illustrate it:

A man was caught mixing horse-meat with chicken. So he was arrested and hauled up before the local beak.

Judge: Do you plead guilty.
A; Yes, my lord.
J: How much horse-meat were you mixing.
A 50:50
J: Please elaborate
A: One horse to one chicken.

So even 5% synth may qualify as semi-synth!

Sir, This sounds like a warning for those who use semi synthetic oil. But , now a days its not that bad from user's perspective. Most of the semi-synth oils advertise as "Synthetic Technology" oil which may be hydro cracked or may be something else which most of us are not aware. I have good experience with Total quartz and Magnatec. I used Servo mineral oil for many years and can not say its bad, in fact it felt more better only con I think that it degrades little faster. Though my experience is limited to petrol engines only. Most of the diesel cars and high end cars now a days recommend to use 5W40 grade which sales as synthetic in India and that too I think because of pollution norms, protection of turbo charger and good cold start. Practically pure synthetic oils like M1, Amsoil etc are designed for high performance engines or rough use and may be for those folks who like red line. Semi synth probably a good deal for those car owners who use their cars seldom or for them who might want to extend change interval for few more kilometers. As I understand the standard 10000 kms or 1 year interval is only theoretical like ARAI FE.Practically in city driving condition average life span of engine oil is 5000 kms. Semi synth users might think that they can extend it till 6000 kms or little more depending upon the oil's quality.
Another experience with M1 0W40 , practically it is good for those cars which recommends xW40 oils like old generation Alto's 10W40. But it can tax on fuel economy for those cars which recommends 5W30 or xW30 oil. Now a days most of the Maruti petrol cars recommend 5W30 oil.

[lapis_lazuli]

Originally Posted by sgiitk

2. No issues with returning to a semi- or even a mineral. I switched from Synth to mineral / semi many times with my old Esteem.

Sir, my Punto petrol has a simple 1.2 liter 8v SOHC engine. It is as simple as it can get but is built to close tolerances: its a FIRE engine. Does its job well with no fuss whatsoever. Needs about 3 liters of oil and the oil doesn't darken or needs a top up, for that matter, even after 5-6k kms post an oil change. It now uses 5W40 semi synth.

FIAT recommends 5W40. It might be mandatory for the 1.3 Multijet, but I was wondering, if I could shift to 10W40. The high temperature viscosity is same for both, but the low temperature extension is lower for the 5W than 10W. (In both cases they are characterized at much less than 0 degrees C.) In NCR we do not have sub zero temperatures. So, can I use 10W40 semi synthetic like the SHELL HX7 10W40? In my limited understanding, it should be usable.

[DriveHigh]

Originally Posted by lapis_lazuli

Sir, my Punto petrol has a simple 1.2 liter 8v SOHC engine. It is as simple as it can get but is built to close tolerances: its a FIRE engine. Does its job well with no fuss whatsoever. Needs about 3 liters of oil and the oil doesn't darken or needs a top up, for that matter, even after 5-6k kms post an oil change. It now uses 5W40 semi synth.

FIAT recommends 5W40. It might be mandatory for the 1.3 Multijet, but I was wondering, if I could shift to 10W40. The high temperature viscosity is same for both, but the low temperature extension is lower for the 5W than 10W. (In both cases they are characterized at much less than 0 degrees C.) In NCR we do not have sub zero temperatures. So, can I use 10W40 semi synthetic like the SHELL HX7 10W40? In my limited understanding, it should be usable.

Hi, 10W40 is an economical option for 5W40. Technically the differences between these two are very less though cold weather engine warm up will be slightly better with 5W40 as I understand. From material data sheet it is hard to predict the effects of such subtle differences. Normally at the time of first ignition of the day it is better to keep idle for around 15 seconds which helps warming up petrol engine slightly.

[nitrous]

Originally Posted by DriveHigh

Hi, 10W40 is an economical option for 5W40. Technically the differences between these two are very less though cold weather engine warm up will be slightly better with 5W40 as I understand. From material data sheet it is hard to predict the effects of such subtle differences. Normally at the time of first ignition of the day it is better to keep idle for around 15 seconds which helps warming up petrol engine slightly.

My friends in the UK with FIRE engine'd cars use this grade.
So, go ahead with it.

[ameyawaghmare]

In the range of brands available for synthetic oil, would it make any difference with the brands? This question comes to mind because towards the beginning of the thread, specifically Mobil1 fully synthetic was recommended.

I have to buy synthetic oil for Fiat Punto 1.2 Actve petrol. I would prefer sourcing online and the items are non-refundable. The 2 options that I have are Shell synthetic 5w40 and Petronas Syntium 3000 SM 5W40 Synthetic Engine Oil.

I am currently on Shell synthetic 5w40 so I have no issues with using that. However, can I opt for the Petronas Syntium? The price of Shell online goes to 4100 while Petronas is costing only 2500, a significant difference! the description of Petronas does not speak if it is for petrol engines or not.

Here is the link to Petronas oil that I am referring.

Please advise as these are non-refundable items with an attached lead time.

[tabrez]

Originally Posted by ameyawaghmare

the description of Petronas does not speak if it is for petrol engines or not.

[url="http://www.amazon.in/Petronas-Syntium-3000-Synthetic-Engine/dp/B00S4IS9CQ/ref=pd_sbs_263_4?ie=UTF8&refRID=0QHBFDPC06D5EPJWXH K5"]

The image on your link speaks of API SM classification & that in my opinion,
should refer to Petrol Engine Oil Service Classification but then again, my
observation is based on an image of the product.

[sgiitk]

@tabrez; Yes API=S? is petrol. There may also be a diesel rating which will be middling at best. Diesels are API-C?.

[ameyawaghmare]

Originally Posted by tabrez

The image on your link speaks of API SM classification & that in my opinion,
should refer to Petrol Engine Oil Service Classification but then again, my
observation is based on an image of the product.

Let's assume this is for petrol cars. However, any explanation for the wide price difference if the technically it is the same oil? If Petronas would be the same as Shell with all specifications, I am no way intent on shelling money for someone's branding!

Looks like I should try this Petronas oil and check the experience myself.

[lapis_lazuli]

A guide, for reference only. For harsh Indian conditions, is 5W40 or lower, really needed? Pic is sourced from benzworld forum. Similar data available from all major oil makers and car-makers.

[sgiitk]

@lapiz_lazuli; The chart is just a generic guide. A lot depends on the tolerances of the manufacturer and his perception. See the Honda Civic, in India they recommend 0W30, while in the US 0w20 is also kosher. Arizona and parts of NM and Calif can be as hot if no hotter. Only the driving conditions may not be that bad in the US. Honda have reportedly allowed 0W20 in some other iVTEC engines here.

[DriveHigh]

0W20, 0W30, 5W30 these grades are being increasingly used in modern petrol and diesel passenger cars in India. Recently I saw in new Alto K10's owner's manual where recommended grade is 0W20 where as earlier version used 5W30 oil. I think manufacturer's decide this grade after meeting certain test criterion for a specific engine in a particular country.