[R2D2]

Originally Posted by Raccoon

May I ask why you change your oil so soon (6 months)? Is it mentioned in the manual? I'm asking because, as I mentioned in a post above, my Esteem's manual advises oil change at 1 year intervals. This is obviously for mineral oils. If you use a synthetic, I dont see why you cant stretch it for a year or so, with your kinda running...

I quite agree about the VFM issue with synth oils. Unless manufacturers bring down prices, I don't see them as a viable option... they just dont make sense. Whats more, they dont even have the right viscosities in the market yet. Sad!

I consider city driving as a severe service conditions. My car manufacturer recommends an oil change at 10K kms or 1 year whichever is earlier OR 5K Kms/6 months which ever is earlier for severe service conditions. Most people think driving in the city at an average speed of 20 KMPH is easy on the car....and boy how wrong they are!

Yes, I can comfortably go for a year or so with a fill of Mobil1 but for 3 things;

a) It may void my warranty. 5W-50 is not a recommended grade neither is Shell Helix 10W-40 though its closer to the recommended 15W-40. I honestly cant take a risk with a 3 month old car.

b) I prefer to have fresh multigrade oil in the sump and a new oil filter every 6 months. I feel the difference after changing the oil after only 4K.

c) Spending about 3.4 grand on an oil change excluding labour makes me wince.

Believe me, I'd shift to synth in a second if I had the correct grade and if the price didnt make me feel I am getting ripped off by Exxon Mobil or Shell.

Foolproof maintenance is to be had by following manufacturers recommended service and oil change intervals. If the Esteem manual says 1 year, then it's great. Just go by the book and you wont go wrong.

Regards,

R2D2

[Raccoon]

Dude, I never implied that stop-go city driving is not a severe service conditon for the oil. Of course it is. I wasn't aware that your use falls into that catageory.

If I were you, I would probably not hesitate much to use a 10W40 (esp. when its synth) when a 10W40 is recommended. But the price of course is another issue.

Foolproof maintenance is to be had by following manufacturers recommended service and oil change intervals. If the Esteem manual says 1 year, then it's great. Just go by the book and you wont go wrong.

I'm not sure thats always true. Because, for one, the manufactuers may not always have his profit in mind rather than whats ideal, etc., etc. Anways, unless we are definite of knowing better, its of course safest to follow it...

[R2D2]

Originally Posted by Raccoon

Dude, I never implied that stop-go city driving is not a severe service conditon for the oil. Of course it is. I wasn't aware that your use falls into that catageory.

If I were you, I would probably not hesitate much to use a 10W40 (esp. when its synth) when a 10W40 is recommended. But the price of course is another issue.

I'm not sure thats always true. Because, for one, the manufactuers may not always have his profit in mind rather than whats ideal, etc., etc. Anways, unless we are definite of knowing better, its of course safest to follow it...

The recommended grades for my car are 5W-30, 10W-30, 15W-40 and 20W-50. The viscosity depends on max expected ambient temperatures. I prefer to stick to what is recommended.

Agreed the company may have profitability in mind. Car manufacturers do not exist because of altruistic beliefs. But who do you trust more? The company that manufactured your car & it's engine or someone else? It is a choice all owners need to make.

[lancer_rit]

Originally Posted by R2D2

a) It may void my warranty. 5W-50 is not a recommended grade neither is Shell Helix 10W-40 though its closer to the recommended 15W-40. I honestly cant take a risk with a 3 month old car.

Usually, the car manual will specify the oil grades required. For my car, 10W-40, 5W-40, and several other grades are allowed. The lower value indicates how low temperatures the oil can work (5W is below 0 deg C already), and the higher number the high temperature. So, in general, 5W-40 can be put in a car which needs 10W-40 with no side effects. Oil companies manufacture for grades which will meet most requirements for a certain geographical/climatic area.

[gpa]

Originally Posted by R2D2

Mobil1 is also available (not in India) in the 10W-30 grade which is what I could use in my current car without warranty issues. But to be on the safe side, the dealers advised me to use the OEM oil as the car warranty is 3 years.

Hi R2D2,

Mobil 1 has the 5W 50 grade and another grade as well in India. I was skeptical too about the warranty of my Alto if I switched to semi-synth or fully synthetic oil. During my last service at 5,000 kms, I asked my service advisor if I could make the switch to semi-synth or fully synth at 10,00 kms and if that would affect my car's 4 year warranty. he assured me that it would not affect the warranty in any manner and that I could go in for either Shell or Mobil 1 or the semi-synth Castrol Magnatec. He said that Mobil 1 fully synthetic oil 5W 50 is far superior when compared to the 20W 40 recommended by MUL in terms of its ability to retain its viscosity at high and low temperatures.

He also cautioned me not to go by claims of dealer of Mobil 1 that just because I was using synthetic oil, I could use it for 15,000 kms or more and said that since my average driving per month was in the range of 1,200-1,500 kms, I would have to change my oil every 6 to 7 months even if I were running on fully synthetic oil.

Regards,

gpa

[Raccoon]

Originally Posted by lancer_rit

Usually, the car manual will specify the oil grades required. For my car, 10W-40, 5W-40, and several other grades are allowed. The lower value indicates how low temperatures the oil can work (5W is below 0 deg C already), and the higher number the high temperature. So, in general, 5W-40 can be put in a car which needs 10W-40 with no side effects. Oil companies manufacture for grades which will meet most requirements for a certain geographical/climatic area.

R2D2, thats why I said 5W40 should be safe enough for your car... anyway its upto you.

He also cautioned me not to go by claims of dealer of Mobil 1 that just because I was using synthetic oil, I could use it for 15,000 kms or more and said that since my average driving per month was in the range of 1,200-1,500 kms, I would have to change my oil every 6 to 7 months even if I were running on fully synthetic oil.

This is quite true, as oil companies are deliberately forumulating their oils to last the same extent as do mineral ones, when they very well can make them last much longer. It is usually the additive package that determines this. If you notice, almost none of them are mentioning on their packs that the oil can be used for longer periods. They obviously dont want you to keep buying their very expensive synthetic oils at the same frequency. One more reason why the synth oils available in India till now, just dont make sense.

And I dont know why you guys are so concerned about the warranty. Do you think you dealer will send a sample of your used engine oil for oil analysis? Lol... Its not at all easy to make out which oil is in the crankase... esp. after it is used a bit! So you know best what to say...

[gpa]

Originally Posted by Raccoon

I dont know why you guys are so concerned about the warranty. Do you think you dealer will send a sample of your used engine oil oil analysis? Lol... Its not at all easy to make out which oil is in the crankase... esp. after it is used a bit! So you know best what to say

Hi Raccoon,

I suppose we were just being cautious on this . Sometimes, these guys at MUL can be quite finicky when it comes to the warranty, especially if you go to them to get something replaced when your nearing the end of your warranty. But my service advisor is knowledgeable enough to keep me informed that the warranty won't be affected.

After all, like you said, I highly doubt that the service dealer will send a sample of your engine oil to MUL to check if it were indeed synthetic or mineral

I will be making the change from mineral oil to Mobil 1 5W 50 this Saturday when my Alto heads for its 10,000 kms service. Will keep you guys posted on the difference in the engine performance.

Regards,
gpa

[sgiitk]

Originally Posted by R2D2

I

5W-50 is not a recommended grade neither is Shell Helix 10W-40 though its closer to the recommended 15W-40. I honestly cant take a risk with a 3 month old car.
R2D2

Let us look at the viscosity issue. W stands for winter grade. Multigrade oils are essentially low viscosity oils with viscosity improvers. 15W40 means that the cold oil is 15W (SAE 15 Winter Grade). 40 means that when hot the oil does not get thinner than SAE40.You need a thin oil in a cold engine for two reasons - ease of starting and fast circulation/lubrication. Thus any oil which has a lower or equal viscosity when cold, and a higher or equal viscosity when hot is Ok. On the contrary when hot the oil should be viscous enough so as not to break the lubricating film. Therefore, a 5W50 definitely meets/exceeds 10W40 or whatever.

Even in the 70's days Esso used to market Uniflo (5W50). I recall having a cold starting problem in my Escort (parked outside) in the UK. This was cured when I switched to Uniflo on the advice of a friend.

[nitrous]

Originally Posted by sgiitk

Let us look at the viscosity issue. W stands for winter grade. Multigrade oils are essentially low viscosity oils with viscosity improvers. 15W40 means that the cold oil is 15W (SAE 15 Winter Grade). 40 means that when hot the oil does not get thinner than SAE40.You need a thin oil in a cold engine for two reasons - ease of starting and fast circulation/lubrication. Thus any oil which has a lower or equal viscosity when cold, and a higher or equal viscosity when hot is Ok. On the contrary when hot the oil should be viscous enough so as not to break the lubricating film. Therefore, a 5W50 definitely meets/exceeds 10W40 or whatever.

Even in the 70's days Esso used to market Uniflo (5W50). I recall having a cold starting problem in my Escort (parked outside) in the UK. This was cured when I switched to Uniflo on the advice of a friend.

Thanks for explaining the science behind grades,Sir.

Mods: This has been discussed in length in the past on the same thread. But,its just unfortunate some of them start this discussion again and again and i don't think it'll stop unless specific posts on the topic of grades is split from here and posted on a new thread that's suitably titled.

[gpa]

Originally Posted by sgiitk

Let us look at the viscosity issue. Therefore, a 5W50 definitely meets/exceeds 10W40 or whatever.

Hi sgiitk,

Very well explained Sir! So it is safe to say that the oils with a rating of 5W 50 and 10W 40 are safe to use in our engines with the 5W 50 grade being slightly better! Guess, we can close our discussion on suitability of engine oils here.

Thanks,
gpa

[Raccoon]

Thus any oil which has a lower or equal viscosity when cold, and a higher or equal viscosity when hot is Ok.

I'm afraid thats not entirely accurate... besides its just looking at one side of the picture. Besides other things, I woudn't use a 5W50 where a 15W40 is recommended. The oil circuits, pump, etc, may not be able to optimally move the oil. Whats more the thicker oil will cause slightly more frictional losses within the engine. Also, when a manufacturer recommends a 'thinner' oil, it usually means that the tolerances of the engine are low, and a thinner oil is required to sufficiently lube all engine parts.

There are many, many other issues which I can point out... but that will take too much typing to come to the same point...

But in short, using 5W40 instead of 10W40 should be ok... as the variation is very small... esp. when using it in a city like Poona... its not a great idea to use a 5W50 where a 10W40 is indicated.

[nitrous]

Originally Posted by racoon

There are many, many other issues which I can point out... but that will take too much typing to come to the same point...
But in short, using 5W40 instead of 10W40 should be ok... as the variation is very small... esp. when using it in a city like Poona... its not a great idea to use a 5W50 where a 10W40 is indicated.

Originally Posted by racoon

Besides other things, I woudn't use a 5W50 where a 15W40 is recommended.

Please justify your statements.

5W50 is superior to 5W40. Which is why its always more expensive than 5W40.
And personally, if I'm going to run my car on the track in summer, I'm not doing it in a 5W40.

[Raccoon]

Dude, firstly I'm not considering lube requirements on a track! Requirements for track and racing and all can be quite different! If you are into racing and all, then I'm sure you know better... so am not gonna discuss racing/track requirements.

I have no idea how you can say a 5W50 is "superiour" to 5W40. They are just different multigrade viscocities, not superiour or inferiour. Just because 5W50 is more expensive does not mean its superiour for your car! The reason why its expensive is very likely beacuse its range is very wide (5 - 50). The manuf whould either have to get a base stock which intrinsically has this much 'width' (not possible in minerals, afaik) and/or have to add VIs, etc, (much less "stable") to make this kind of oil upto specification. Now thats likely to cost more money. So if your car does not need thicker oil, then all this is just no use to you.

I have already partly justified what I have said in the last post. As I said, there is a lot more, but to explain all will take too much typing. Anyone intrested could find the same thing in some comprehensive litreture on lube oils.

Lastly, I'm sure you have observed the trend towards thinner oils, in the auto industry. Hasn't anyone wondered why this is so??

So, once again, using a thicker oil than what is required is of no benifit. In fact it may cause harm in the long term.

Thicker oils (like Xw50) are usually recommended for old cars (high tolerances), or cars with worn engines, that are consuming more oil, etc.

[nitrous]

Originally Posted by raccoon

The reason why its expensive is very likely beacuse its range is very wide (5 - 50).

So, the 5w50 does the job of 5w40 and more.
IIRC, xW40 is stable upto 35 degree Centigrade(ambient temperature).
Now,people have been running engines on 15W40 and 20W40/50 for decades. There has been significant engine damage in summers because most of the production engines were tuned for reliability/daily drives rather than race tolerances/high BHP.
I will accept that 5W50 is not required unless you're revving the guts out of the engine in 40-45 Degree C(very hot summer afternoon) or you're worried about the european engine in tropical summers.
For summers, I'd suggest 15W50(very rare) or 5W50 (pricey).
Or you could use 5W40 and not rev too high.

Edit: I just noticed we already have a thread on this topic and I've given my inputs already: http://www.team-bhp.com/forum/techni...5w40-5w50.html

[Raccoon]

If you are using 5w50, then im assuming its synthetic... cus afaik, you cant make a mineral oil of that viscosity thats 'stable'. Now a real synthetic inherently is thermally far more stable... it shouldnt thin out beyond its specification. So then why not use a 5w40 if thats what is recommended(fully synth)?? I REALLY doubt that an xW40 synth oil will thin out and not provide enuf lubrication, even in track situations...

What you are saying could be quite true for a mineral oil. A 20W50 mineral oil for eg., very well may 'break down' under extreme track conditions in summer.... but I really dont feel a true synth (PAO/Easter based) xW40 will fail. Also know that using a xW50 instead of xW40 (where the latter is recommended by manuf) may reduce bike performance to a slight extent. But that slight loss you might not afford, when you are in a race...

Thats what I feel. Its for you to accept/reject it, based on your experience on the track.

Btw, this engine damage on track+summber that you are talking about... did it happen when using a true synthetic?? I suspect it must have been dino oil... or not a true synth at least.