Everything you have to know about engine oil tread.................................

Great idea to start this thread, thanks Roel!

I use (to be honest, my garage master):
Castrol Formula RS 10W-60

http://www.castrol.com/castrol/productdetailmin.do?categoryId=82916346&contentId=6004594

 

I always used AGIP 10W60 in my Ferrari. There have been some great threads about this in the past (technical section).

Ton

 

We have had some interesting info on our Caterhan race car site, it's worth reading....................

My name is Simon Barnard and I'm in the oil business. I've been watching the oil related threads here for some time and they are interesting reading. I felt that you should be aware of the difference between synthetic oils mainly due to the Mobil/Castrol courtcase in the US and the labelling issues that it created. Basically any oil which is not "synthetic" in the true sense of the word I.E. created in a laboratory by chemists and not related to petroleum (Hydrocracked or Mineral Oil) can now be legally labelled as synthetic even though is is "molecularly moified" mineral oil.

This has profound quality issues for those seeking "superior" true synthetic oils as many cans on the shelves labelled synthetic are simply poorer cousins of the real thing being PAO, Ester or a blend of the two.

If you'd like to learn more then read on as this will explain the differences and they are very different!

“HYDROCRACKED” (HC) or MOLECULARLY CONVERTED (MC) BASESTOCKS

There are many petroleum oils available on the market that are so pure and refined, they can now be passed off as synthetics.
They are not made from true synthetic basestocks (at least not in the way that synthetics have traditionally been defined), but they have so little in common with traditional petroleum basestocks, it is really somewhat silly to classify them as petroleum oils. Petroleum oil basestocks can be put through a super-extreme refining process called “hydrocracking”. In some cases, as in the case of one particular name-brand "synthetic" oil, these highly refined petroleum basestocks can actually be termed and sold as "synthetic".
It is completely legal for lubricants manufacturers to label these oils as "synthetic".

These are extremely high performance petroleum basestocks, but they are not truly synthetic the way that most people understand the term and will not necessarily perform to the same level as a premium synthetic oil like PAO (poly alfa olefins) or Esters.

Hydrocracking involves changing the actual structure of many of the oil basestock molecules by breaking and fragmenting different molecular structures into far more stable ones. This results in a basestock which has far better thermal and oxidative stability as well as a better ability to maintain proper viscosity through a wide temperature range - when compared to a typical petroleum basestock.

Although contaminants are still present, and these are still petroleum basestocks, contamination is minimal and performance characteristics are high. This process also can turn a wider range of crude oil stock into well-performing petroleum lubricant basestocks.

TYPES OF SYNTHETIC BASESTOCKS

Synthetic basestocks are not all the same. There are few different chemical types that may be used as synthetic basestock fluids. There are only three that are seen commonly in automotive applications:

Polyalphaolefins (PAO's)
These are the most common synthetic basestocks used in the US and in Europe. In fact, many synthetics on the market use PAO basestocks exclusively. PAO's are also called synthesized hydrocarbons and contain absolutely no wax, metals, sulfur or phosphorous. Viscosity indexes for nearly all PAO's are around 150, and they have extremely low pour points (normally below –40 degrees F). Although PAO's are also very thermally stable, there are a couple of drawbacks to using PAO basestocks. One drawback to using PAO's is that they are not as oxidatively stable as other synthetics. But, when properly additized, oxidative stability can be achieved.

Diesters
These synthetic basestocks offer many of the same benefits of PAO's but are more varied in structure. Therefore, their performance characteristics vary more than PAO's do. Nevertheless, if chosen carefully, diesters generally provide better pour points than PAO's (about -60 to -80 degrees F) and are a little more oxidatively stable when properly additized. Diesters also have very good inherent solvency characteristics which means that not only do they burn cleanly, they also clean out deposits left behind by other lubricants - even without the aid of detergency additives.
They do have one extra benefit though, they are surface-active (electrostatically attracted to metal surfaces), PAO’s are not “polar”, they are “inert”.

Polyolesters
Similar to diesters, but slightly more complex. Greater range of pour points and viscosity indexes than diesters, but some polyolester basestocks will outperform diesters with pour points as low as -90 degrees F and viscosity indexes as high as 160 (without VI additive improvers). They are also “polar”.

Other synthetic basestocks exist but are not nearly as widely used as those above - especially in automotive type applications. Most synthetics on the market will use a single PAO basestock combined with an adequate additive package to provide a medium quality synthetic lubricant. However, PAO basestocks are not all the same. Their final lubricating characteristics depend on the chemical reactions used to create them.

Premium quality synthetics will blend more than one "species" of PAO and/or will blend these PAO basestocks with a certain amount of diester or polyolester in order to create a basestock which combines all of the relative benefits of these different basestocks.

This requires a great deal of experience and expertise. As a result, such basestock blending is rare within the synthetic lubricants industry and only done by very experienced companies. In addition, although such blending creates extremely high quality synthetic oils, they don't come cheap. You get what you pay for! Or do you?


AND

It’s written on every can of oil and it’s the most important visible characteristic of an oil.
The viscosity of an oil tells you how it reacts in certain circumstances and how it performs as a lubricant.
When a oil is subjected to external forces, it resists flow due to internal molecular friction and viscosity is the measure of that internal friction. Viscosity is also commonly referred to as the measurement of the oils resistance to flow.

There are two methods of viewing an oils resistance to flow. Firstly there is Kinematic Viscosity which is expressed as units indicating the flow of volume over a period of time and this is measured in centistokes (cSt).
An oils viscosity can also be viewed by measured resistance. This is known as Apparent Viscosity and it is measured in centipoises (cP).

However in the real world an oils viscosity is also referred to in such terms as thin, light and low etc. This suggests that the oil flows or circulates more easily. Conversly, terms such as heavy and high etc suggest the fluid has a stronger resistance to flow.

The reason for viscosity being so important is because it is directly related to the oils load-carrying ability - The greater an oils viscosity, the greater the loads that it can withstand. (It must be added when new not over a period of time as all oils “shear down” with use)

An oil must be capable of separating the moving parts in your engine at the operating temperature. On the basis that an oils viscosity is related to its load carrying ability, you could be fooled into thinking that “thicker” oils are better at lubricating but, you’d be wrong in this assumption. The fact is that in the wrong application a high viscosity oil can be just as damaging as using a low viscosity oil.

The use of an oil that’s too “thin” can cause metal-to-metal contact, poor sealing and
increased oil consumption and conversely, an oil that’s too “thick” can cause increased friction, reduced energy efficiency, higher operating temperatures, and poor cold starts in cold temperatures.

It is very important that you select the correct oil, not too “light” or too “heavy” and your Owners Handbook is a very good place to start as it lists the temperatures and options.

Oils thicken at low temperatures and thin as the temperature increases. The actual rate of change is indicated by their viscosity index (this number normally listed on the oils technical data sheet indicates the degree of change in viscosity of an oil within a temperature range, currently 40-100 degrees centigrade)

An oil with a high viscosity index, will normally behave similarly at these two temperatures but an oil with a low viscosity index will behave quite differently. It will become very fluid, thin and pour easily at high temperatures. A higher index is better!

Multi-grade oils are designed to perform at high and low temperatures by adding polymers to a base oil (5w,10w, 15w etc) which are heat sensitive and “uncoil” to maintain the higher viscosity sae 30,40,50 etc. This means that the oil can be used “all year round” rather than using different oils for summer and winter.

It is important to understand that the selection of the correct oil for your car is not just guesswork, you must consider the temperatures at which you need the oil to operate a 0w, 5w oil is better for cold starts as the oil circulates more easily when it’s cold and is able to flow around the engine more easily and quickly, offering protection at the critical moments following cold engine start-up. These oils are also known to give better fuel economy and engine performance.

Finally, all oils “shear” or thin down with use and this means that an oil that started life as a 10w-40 will with use become a 10w-20. The period of time this takes depends on the type and quality of the oil. The most “shear stable” oils are proper Synthetics, either PAO (Poly Alph Olefins) or Esters which have very high thermal stability. They are in general of the more expensive variety but last longer and give the best levels of protection.


AND

Ok, I wish it was so simple but it's not going to be but there are some good facts (Mr Carmichael) in particular and some very confused people here.

Let's start with some basics:

Viscosity is not the be all and end all of oil, "shear stability" is more important. You see a non true synthetic 5w-50 will degrade in a very short space of time (a couple of thosand miles) which means that it could be a 5w-30 with use. It's the use that sorts them out!

Why is this? Well you see "hydrocracked" oils need more additives especially VI improvers to prop them up and these additives tend to break down "shear" with use which means that they are unable to keep the oil thick enough.

The most "shear stable" oils are true synthetics, created in laboratories by chemists and have no relation to petroleum (hydrockracked) oils and they are more thermally stable to start with so less additives are required so they don't break down so easily.........Following me?

So my advice would be to use a "shear stable" proper synthetic oil either PAO or Ester basestock or PAO/Ester blend which will be tougher and protect better. In this case and only using this type of oil I would recommend a 5w-40 Fully Synthetic.

This will give you flow when cold 5w and a very thermally stable sae 40 which will not breakdown after a couple of thousand miles.

Is an sae 50 required? Well I could put arguments forward for this but once again a true synthetic would be best and possibly a 10w-50 would suit people doing mad things with their cars as it will give outstanding protection at high temperatures without breaking down although some cold start sacrifices would be made using 10w.

Selecting the correct oil is more technical than most people realise and understanding which is best is not simple but hopefully the following will explain some of the reasons why you should try to stay in grade as best possible.

Surely the thicker the oil the better!

This isn't always true - even when using a petroleum oil. Although it is true that
heavier viscosity oils (which are generally thought of as being thicker) will hold up better under heavy loads and high temperatures, this doesn't necessarily make them a better choice for all applications.
On many newer vehicles only 0w-40, 5w40 or 10w40 engine oils are recommended by the
manufacturer. If you choose to use a higher viscosity oil than what is recommended, at the very least you are likely to reduce performance of the engine. Fuel economy will likely go down and engine performance will drop.
In the winter months it is highly recommended that you not use a heavier grade oil than what is recommended by the manufacturer. In cold start conditions you could very well be causing more engine wear than when using a lighter viscosity oil. In the summer months, going to a heavier grade is less of an issue, but there are still some things to be aware of.

Moving one grade up from the recommended viscosity is not likely to cause any problems (say from a 10w40 to a 10w50 oil). The differences in pumping and flow resitance will be slight. Although, efficiency of the engine will decrease, the oil will likely still flow adequately through the engine to maintain proper protection. However, it will not likely protect any better than the lighter weight oil recommended by the manufacturer.
Moving two grades up from the recommended viscosity (say 10w40 to 10w-60) is a little more extreme and could cause long term engine damage if not short term. Although the oil will still probably flow ok through the engine, it is a heavier visocosity oil. As such it will be more difficult to pump the oil through the engine. More friction will be present than with a lighter viscosity oil. More friction will be present than with a lighter viscosity oil. More friction means more heat. In other words, by going to a thicker oil in the summer months, you may actually be causing more heat build-up within the engine. You'll still be providing adequate protection from metal to metal contact in the engine by going with a high viscosity, but the higher viscosity will raise engine temperatures.
In the short run, this is no big deal. However, over the long term, when engine components are run at higher temperatures, they WILL wear out more quickly. As such, if you intend on keeping the vehicle for awhile, keep this in mind if you're considering using a heavier weight oil than the manufacturer recommends.
The best advice is to is to stay away from viscosity grades that are not mentioned in your owner's manual unless you are running an entirely differently set up car in which case seek professional advice.

No meaning to plug my company but we supply 5 brands of oil and we understand what constitutes a good one. If you want a good ester/pao "shear stable" oil then look here at Silkolene PRO S.

AND LASTLY

With regards to the benefits of "true" synthetics as opposed to "hydrocracked" or molecularly converted mineral oils these are the main ones.

Stable Basestocks

Synthetic oils are designed from pure, uniform synthetic basestocks, they contain no contaminants or unstable molecules which are prone to thermal and oxidative break down.
Moreover, because of their uniform molecular structure, synthetic lubricants operate with less internal and external friction than petroleum oils which have the non-uniform molecular structure. The result is better heat control, and less heat means less stress to the lubricant.

Higher Percentage of Basestock

Synthetic oils contain a higher percentage of lubricant basestock than petroleum oils do.
This is because multi-viscosity oils need a great deal of pour point depressant and viscosity modifying additives in order to be sold as multi-viscosity oils.
Synthetic oils, require very little in the way of pour point depressants and viscosity
modifiers. Therefore, synthetic oils can contain a higher percentage of basestock, which actually does most of the lubricating anyway. More basestock leads to longer motor oil life.

Additives Used Up More Slowly

Petroleum basestocks are much more prone to oxidation than synthetic oils, oxidation inhibitors are needed in greater supply and are used up very quickly. Synthetic oils do oxidize, but at a much slower rate therefore, oxidation inhibiting additives are used up much more slowly.
Synthetic oils provide for better ring seal than petroleum oils do. This minimizes blow-by and reduces contamination by combustion by-products. As a result, corrosion inhibiting additives have less work to do and will last much longer than within a petroleum oil.

Excellent Heat Tolerance

Synthetics are simply more tolerant to extreme heat than petroleum oils are. When heat builds up within an engine, petroleum oils quickly begin to burn off. They volatize. In other words, the lighter molecules within petroleum oils turn to gas and what's left are the large petroleum oil molecules that are harder to pump. Synthetics are resistant to this burn-off. They will tolerate much higher engine temperatures.

Heat Reduction

More often than not, vehicle life is determined by engine life. One of the major factors affecting engine life is component wear and/or failure, which is often the result of high temperature operation. The uniformly smooth molecular structure of synthetic oils gives them a much lower coefficient of friction (they slip more easily over one another causing less friction) than petroleum oils. Less friction, of course, means less heat in the system. And, since heat is a major contributor to engine component wear and failure, synthetic oils significantly reduce these two detrimental effects. In addition, because of their uniform molecular structure, synthetic oils do not cause the "blanket effect" which was mentioned earlier. Since each molecule in a synthetic oil is of uniform size, each is equally likely to touch a component surface at any given time, thus moving a certain amount of heat into the oil stream and away from the component. This makes synthetic oils far superior heat transfer agents than conventional petroleum oils.

Greater Film Strength

Petroleum motor oils have very low film strength in comparison to synthetics. The film strength of a lubricant refers to it's ability to maintain a film of lubricant between two objects when extreme pressure and heat are applied. Synthetic oils will typically have a film strength of 500% to 1000% higher than petroleum oils of comparable viscosity. In fact, believe it or not, even though heavier weight oils typically have higher film strength than lighter weight oils, a 0w30 or 5w-40 weight synthetic oil will likely have higher film strength than a 15w40 or 20w50 petroleum oil.
Thus, even with a lighter weight oil, you can still maintain proper lubricity and reduce the chance of metal to metal contact when using a synthetic oil. Of course, that means that you can use oils that provide far better fuel efficiency and cold weather protection without sacrificing engine protection under high temperature, high load conditions. Obviously, this is a big plus, because you can greatly reduce both cold temperature start-up wear and high temperature/high load engine wear using the same low viscosity oil.

Engine Deposit Reduction

Petroleum oils tend to leave sludge, varnish and deposits behind after thermal and oxidative break down. They're better than they used to be, but it still occurs. Deposit build-up leads to a significant reduction in engine performance and engine life as well as increasing the number of costly repairs that are necessary. Since synthetic oils have far superior thermal and oxidative stability than petroleum oils, they leave engines virtually varnish, deposit and sludge-free.

Better Cold Temperature Fluidity

Synthetic oils and other lubricants do not contain paraffins or other waxes which dramatically thicken petroleum oils during cold weather. As a result, they tend to flow much better during cold temperature starts and begin lubricating an engine almost immediately. This leads to significant engine wear reduction, and, therefore, longer engine life and fewer costly repairs.

IMPROVED FUEL MILEAGE AND PERFORMANCE

As indicated earlier, synthetic oils, because of their uniform molecular structure, are tremendous friction reducers. Less friction leads to increased fuel economy and improved engine performance.
Any energy released from the combustion process that would normally be lost to friction can now be transferred directly to the wheels, providing movement.
Vehicle acceleration becomes swifter and more powerful while using less fuel in the process.
The uniform molecular structure of synthetic oils has another performance enhancing benefit as well. In a petroleum oil, lighter molecules tend to boil off easily, leaving behind much heavier molecules which are difficult to pump. Certainly, the engine loses more energy pumping these heavy molecules than if it were pumping lighter ones. Since synthetic oils have more uniform molecules, fewer of these molecules tend to boil off. More importantly, when they do, the molecules which are left are of the same size and pumpability is not affected.

 

Oil strategy key to Ferrari reliability in 2005.... http://www.auto123.com/en/info/news/racing,view.spy?artid=36705

MARK

 

MONSTER INPUT
....all we wanna know, thanks a lot!

 

That' what I got when I searched "Oil" and "Ferrari" on Google!! Oh well - at least I tried! MARK

 

That is......I know NOTHING about lubricants (except for certain types) MARK

 

Thats why we have ROBERT F.!

 

B U M P !

 

You all are aware about the threads from Ali E. Haas about engine oil?

 

Mark, that was one of the most informative presentations that I have seen that gives it to you in an effective straight forward manner.
Would you reveal what basestocks are used by the different major syn. oil producers?

Best regards

Gary

"I have never let my schooling interfere with my education"