Technical Oil in my Fiat!

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Technical Oil in my Fiat!

ahmett

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Ok guys sorry I am not a mechanic and i like driving cars based on instinct. Now Fiat says 5w40 C3 style must be used for refilling the oil.
I am looking around online and i am seeing 5w30 being more common or even 0w30.

When will we know that the manual saying 5w40 will be outdated with the continuous advance of motor engine oil technology? And of course when the warranty is over, what oil will we know is best for the engine given that when they built the engine the oil tech was older?

I know some of you will say only stick to the manual and never deviate but some out of the box thinking perhaps anyone?


In a basic 5 year old answer, whats the difference of different oils?


Thank you for helping and sorry if these questions sound ignorant to the techs on the forum.
 
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Ok guys sorry I am not a mechanic and i like driving cars based on instinct. Now Fiat says 5w40 C3 style must be used for refilling the oil.
I am looking around online and i am seeing 5w30 being more common or even 0w30.

When will we know that the manual saying 5w40 will be outdated with the continuous advance of motor engine oil technology? And of course when the warranty is over, what oil will we know is best for the engine given that when they built the engine the oil tech was older?

I know some of you will say only stick to the manual and never deviate but some out of the box thinking perhaps anyone?

In a basic 5 year old answer, whats the difference of different oils?

Thank you for helping and sorry if these questions sound ignorant to the techs on the forum.

I cannot see Fiat changing the recommendation of 5w40. Also regular changes of the oil will keep its viscosity correct as opposing to getting thicker which it does as it gets older.;)

There's a few meaty threads on here on oil but in relation to your 1368cc engine pre multi-air it will need 5w40 C3 since the tolerances that the engine was built to is not 'designed' for a a thinner oil.
Given the type of driving that some do going to the red line on a regular basis you will need the protection of the '40' particularly in a 'warmer' climate.
Some have used 0w40 Mobile 1 as a cleansing oil but again not recommended. I used this incorrectly on one occasion but it was changed pretty quickly.
I would consider some of the newer breed 5w30 C2/C3 where the C2 is an 'economy' type oil in a NA engine (i.e. not turbo charged). This spec oil is what is also used in the MJ but it is still not recommended.
 
Ahmett, I'm thinking you may have opened up a right can of worms.

For most of the people, most of the time, keeping it simple & sticking with the manufacturer's recommendation will keep you out of trouble.

That said, there's a bit of a "one size fits all" feeling to a recommendation which has to cover all driving styles across diverse geographical markets where typical ambient temperatures could be anywhere from -10C to +40C.

So, picking up on:

...but some out of the box thinking perhaps anyone?

I'll start by saying there are some sound technical reasons (on a normally aspirated petrol 500) for changing to an 0W30 oil when average temperatures are likely to be below 10C, if the car is used primarily for commuting and sustained high speed operation is avoided.

Winter oil thread, anyone :rolleyes:.
 
Ahmett, I'm thinking you may have opened up a right can of worms.

For most of the people, most of the time, keeping it simple & sticking with the manufacturer's recommendation will keep you out of trouble.

That said, there's a bit of a "one size fits all" feeling to a recommendation which has to cover all driving styles across diverse geographical markets where typical ambient temperatures could be anywhere from -10C to +40C.

So, picking up on:



I'll start by saying there are some sound technical reasons (on a normally aspirated petrol 500) for changing to an 0W30 oil when average temperatures are likely to be below 10C, if the car is used primarily for commuting and sustained high speed operation is avoided.

Winter oil thread, anyone :rolleyes:.
Pretty much.

I'll stick with 5w40 thanks. In a hot climate like greece, perhaps go for a 10w40
 
I think Ahmett wants to know what the differences are between oils and what the numbers and letters mean, as well as knowing which he can use.
 
It occurs to me that I neither know nor really care what the C2, C3 etc things mean. I use generic 5w30 and nothings gone boom in 75k miles of driving. Read into that what you will. :)
 
It occurs to me that I neither know nor really care what the C2, C3 etc things mean. I use generic 5w30 and nothings gone boom in 75k miles of driving. Read into that what you will. :)

I'd read into it that there's an awful lot of b******s talked about oil. IMO changing it frequently is much more important than which brand you use. My engine core was most likely originally designed to run on 20w-50 mineral oil changed every 6k & I'd be surprised if the mechanical tolerances have ever been altered in the intervening decades.
 
Pretty much.
I'll stick with 5w40 thanks. In a hot climate like greece, perhaps go for a 10w40

I've only seen a 10w40 in semi synthetic but there is the 'Abarth' synthetic oil in 10w50 and in a turbo charged car it would be recommended particularly in a 'hotter' climate.

I think Ahmett wants to know what the differences are between oils and what the numbers and letters mean, as well as knowing which he can use.

I've struggled a bit with getting a handle on the 'numbers' and standards do appear to be changing. On the 'graph' for the ACEA C2 you can see how it 'leans' towards economy.
http://www.lubrizol.com/EuropeanEngineOils/C208.html
http://www.lubrizol.com/EuropeanEngineOils/C308.html
http://www.driverstechnology.co.uk/oils.htm
ACEA
This is the European equivalent of API (US) and is more specific in what the performance of the oil actually is. A = Petrol, B = Diesel and C = Catalyst compatible or low SAPS (Sulphated Ash, Phosphorus and Sulphur).

It occurs to me that I neither know nor really care what the C2, C3 etc things mean. I use generic 5w30 and nothings gone boom in 75k miles of driving. Read into that what you will. :)

When I compared the 'wear' test between a 5w30 and a 5w40 the difference is very small ...
https://www.fiatforum.com/500/286912-oil-change-9.html?p=2903216
http://www.mobil1.co.uk/synthetic-engine-oils/esp-formula-5w-30.aspx

I still would use the 5w40 viscosity in Greece if I regularly red line and don't do regular oil changes. IIRC Jason does oil changes every 5K ?
 
I think Ahmett wants to know what the differences are between oils and what the numbers and letters mean, as well as knowing which he can use.

He'll probably get more useful information by trawling the internet than reading our ramblings. Here's one place to start:

http://www.driverstechnology.co.uk/oils.htm

Note: posted before reading loveshandbags post above
 
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I'd read into it that there's an awful lot of b******s talked about oil. IMO changing it frequently is much more important than which brand you use. My engine core was most likely originally designed to run on 20w-50 mineral oil changed every 6k & I'd be surprised if the mechanical tolerances have ever been altered in the intervening decades.

The 1368cc engine was originally designed to run on semi synthetic 10w40 but then 'changed' to 5w40. From the bit of research that I did I learned that there was an optimum change for 'normal' users i.e. not track use and it was 8K miles.

Anyway - it's all been covered before and so there's no point in going over 'old ground'.:)

https://www.fiatforum.com/500/286912-oil-change-9.html?p=2902591
Came across this study (click here) that was carried out on oils and how they 'wear' before they 'ran out of money'. Before some of the findings 'get shot to pieces' I thought I'd post some videos. There's quite a bit of 'reading' but it can be summarised with...
we believe engine builders spec an oil for a reason, and this oil is far, far thicker now than intended for the ...
 
You know what i still dont exactly understand the difference of 5w30 and 5w40? 40 is thicker yeah? So what is better thicker or thinner?
 
like I said, you want a 10w40 or 5w40, not a 0w40. That would be for countries that have very cold winters
 
Well i just finished my 1l top up 5w-40 so I think I will stick with 5w-40 until my next oil change in 20,000 km.
 
Also regular changes of the oil will keep its viscosity correct as opposing to getting thicker which it does as it gets older.;)

It gets thinner (particularly at operating temperature), when it has been used in an engine for some miles - because of the loads the oil molecules are subjected to, effectively shearing them apart and breaking them up. It is the long chains of polymers in the oil that give it the viscosity..
 
It gets thinner (particularly at operating temperature), when it has been used in an engine for some miles - because of the loads the oil molecules are subjected to, effectively shearing them apart and breaking them up. It is the long chains of polymers in the oil that give it the viscosity..

Excuse the long post (this is die hard territory :eek:)

Just to clarify about oil as it ages getting thicker - it does get thinner as you rightly pointed out but then gets thicker. I'm not too sure if that was what you were saying but here is a few references to back it up. I included a 'reference' to your 'polymers' towards the end. In the last article they were dubious about the real benefits of 'economy oil' and on balance preferred to increase the 'base' viscosity.

The source for this might be a bit dubious…
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1489572 (#1489905 - 06/06/09 04:40 PM)
The general pattern for engine oils is to shear a bit thinner, then get thicker when they are really beat up and old.

http://ferrarichat.com/forum/faq.php?faq=haas_articles
The reality is that motor oils do not need to be changed because they thin with use. It is the eventual thickening that limits the time you may keep oil in your engine. The limit is both time itself (with no motor use) and/or mileage use. The storage of motor oil in your garage, particularly mineral based oils, slowly ages the oil limiting its use later. Do not store huge volumes of oil in your garage that is exposed to extremes of temperature.
Motor oil becomes permanently thicker with exposure to northerly winter type weather.

http://neptune.spacebears.com/cars/stories/amsoil.html
Mile 8000 -- Bryan Savage, May 1, 2004.
Oil/Vehicle miles: 8,130 / 39,106
Oil added after sample: none

A road trip caused us to miss our sample by a hair over 100 miles. At this point the oil looks black, like used oil ought to. It also continues to thicken up, and is now officially a 5W40 oil instead of the 5W30 we poured in there.
Mile 13,000 -- Jochen Lellesch, November 5, 2004.
Oil/Vehicle miles: 13,001 / 43,977
Oil added after sample: none

Ah, the second-to-last sample. By rights it should be the absolute last sample, but we're going to spot Amsoil one more after this. At 13,000 miles, Amsoil continues to hold steady -- clearly, Amsoil can last much longer than we initially thought possible. That is provided, of course, that you have no problem with the oil thickening way out of grade (many people don't, which is why we continued the test despite our own reservations about it now being a solid 40-weight oil). Well, one more sample to go, and then we'll enter the next flush period, which should settle whether the oil is contributing to the fuel economy drop.

There’s a good summary at the end…
http://www.machinerylubrication.com/Read/518/motor-oils
Another factor in fuel economy is temporary polymer shear. These polymers are additives known as viscosity index improvers (or modifiers). Polymers are plastics dissolved in oil to provide multiviscosity characteristics. Just as some plastics are tougher, more brittle or more heat-resistant than others, different polymers have different characteristics.
Polymers are huge molecules with many branches. As they are heated, they uncoil and spread out. The branches entangle with those of other polymer molecules and trap and control many tiny oil molecules. Therefore, a relatively small amount of polymer can have a huge effect on oil viscosity.
As oil is forced between a bearing and journal, many polymers have a tendency to align with each other, somewhat like nesting spoons. When this happens, viscosity drops. Then when the oil progresses through the bearing, the polymer molecules entangle again and viscosity returns to normal. This phenomenon is referred to as temporary shear.
..........
The best protection against wear is probably a product that is a little thicker (such as SAE 10W-30 or 15W-40) and has more antiwear additives than the oils that support the warranty. The best oil for your vehicle depends on your driving habits, the age of your engine and the climate you drive in, but it is not necessarily the type of oil specified in the owner’s manual or stamped on the dipstick.

So in a nutshell 5w40 as per manufacture's recommendation and it also explains why Fiat increased the viscosity to 10w50 for the Abarth models.
 
Very nice, wheeling out google for the answers ;)

Seriously, if the oil is thicker due to old age, you are *seriously* tight fisted, or lazy, because it has to be left in there for absolutely ages beyond it's change interval to go like that. The one article about amsoil you mention above where it talks about 100 miles over interval is, in my experience, complete crap. Maybe one in a million, but for most, no.

Bear in mind that the Yanks are obsessed about oil changes, too, so take what they say with a large pinch of sodium chloride, specifically when you're talking about Fiat Powertrain products.
 
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Very nice, wheeling out google for the answers ;)

Seriously, if the oil is thicker due to old age, you are *seriously* tight fisted, or lazy, because it has to be left in there for absolutely ages beyond it's change interval to go like that. The one article about amsoil you mention above where it talks about 100 miles over interval is, in my experience, complete crap. Maybe one in a million, but for most, no.

Bear in mind that the Yanks are obsessed about oil changes, too, so take what they say with a large pinch of sodium chloride, specifically when you're talking about Fiat Powertrain products.

I only posted a 'snap shot' of what's out there. :eek: The amsoil case study was posted before but it was under the Mobil one study. Anyway, you are probably one of the few that would be 'able to get into it' since TBH I was getting out of my depth. The only 'gem' that I got was from the Mobile one study that by topping oil up you can extend the 'life' of the oil plus there seemed to be an optimium time to change the oil.

Anyone it just goes to prove that you can find the 'right' answers if you look hard enough :p but I would agree with you that oil gets thinner as it deteroriates. I can only think that when it gets to a 'thick' stage it must be full of junk.(y)
 
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Exactly - it's full of sludge, and I'd hate to look at the filter of an engine that contains such stuff. Usually they're completely blocked and just lift the bypass valve every time the engine starts, otherwise they collapse, both ways = no filtration.

Definitely change your oil at that point :)
 
I still would use the 5w40 viscosity in Greece if I regularly red line and don't do regular oil changes. IIRC Jason does oil changes every 5K ?

As I stare at the box of a dozen oil filters on the shelf and contemplate my obsessive nature, yes, I am compelled to admit that I change oil often :)
 
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