16 replies to this topic

[sinister]

One thing that really interests me is the things behind the labels and marketing of various products, and today this is oils.

A little fact some may not know is most "synthetic" oils are not a synthetic oil. There are many oils out there that call themselves synthetic, but not all are created equal, and that's important to know. You do get what you pay for. Group 3 synthetic oils only use about 12% synthetic base stocks. The rest is hyrdocracked petroleum (crude oil) base stocks. For major oil companies who have their money in crude oil refining, the word "synthetic" is merely a marketing term. It does not mean 100%, but just that a percentage of synthetic base stock goes into their product.

In the late 1990s, Castrol started selling an oil made from Group 3 base oil and called it SynTec Full Synthetic. Mobil sued Castrol, asserting that this oil was not synthetic, but simply a highly refined petroleum oil, and therefore it was false advertising to call it synthetic. In 1999, Mobil lost their lawsuit. It was decided that the word "synthetic" was a marketing term and referred to properties, not to production methods or ingredients. Castrol continues to make SynTec out of Group 3 base oils, that is highly purified mineral oil with most all of the cockroach bits removed. Shortly after Mobil lost their lawsuit, most oil companies started reformulating their synthetic oils to use Group III base stocks instead of PAOs or diester stocks as their primary component. Most of the "synthetic oil" you can buy today is actually mostly made of this highly-distilled and purified dino-juice called Group 3 oil. Group 3 base oils cost about half as much as the synthetics. By using a blend of mostly Group 3 oils and a smaller amount of "true" synthetics, the oil companies can produce a product that has some of the same properties as the "true" synthetics, and nearly the same cost as the Group 3 oil.

True synthetic oils are not refined, they are created, so each litre is identical to the next and the one before it. Within each litre, all the molecules are the same - there are no weak points. Since every drop of synthetic oil in your engine degrades at the same pace, this greatly reduces the sludge deposits left behind from broken down oil.

Engineered to perform uniformly, synthetic oils have none of the molecular surprises that conventional oils do. In the ground, natural oil can be tainted by a variety of substances. While most of this is removed by the refining process, some of it is left behind and become the Achilles' heel of your engine's protection. These weak points degrade faster than most of the other parts of the oil and build up inside your engine. If you have ever looked at a used oil pan, or engine, all that black sludge is left is from degraded oil.

A true synthetic oil also tolerates extreme temperatures, which are experienced in all modern motors, far better than a mineral based oil. This increased tolerance to boiling reduces oil consumption and leaves more oil in your engine to protect it.

The oils that are commonly mentioned are Group 2 and Group 3 synthetics with the exception of Royal Purple, which is a Group 4.

Another type of base oil is made from refined and processed esters and is called Group 5.

Esters start life as fatty acids in plants andanimals, which are then chemically combined into esters, diesters, and polyesters. Group 5 base stocks are the most expensive of all to produce. However, the esters are polar molecules and have very significant solvent properties - an ester base oil all by itself will do a very decent job of keeping your engine clean. So, people who are serious about making a superior oil will usually mix some Group 5 oils into their base stock.

Oils that are strictly Group 5 ester oils tend to be better suited for high RPM, hot running, air cooled engines. 100% ester based oils are usually more expensive than Group 4 oils, and don't have the longevity of PAO (Group 4) or PAO/Ester mixes oils. Group 5 oils perform very well in the shorter term. Oils like Royal Purple and Redline are Group 5 oils. They perform very well in race engines and in applications where drain intervals are factory spec or shorter, whereas Group 4 oils are better suited for the long haul of extended intervals. Whatever oil you choose, know what you are buying. Just because the jug says "synthetic" doesn't mean it is made from 100% pure syntheticbase stocks.

[Swiftpimp]

speaking of Redline oil, anyone know where i can get my hands on the good stuff? im chasing water wetter and oil

[cantthinkofone]

Interesting Read. Didn't know much of that. Just out of curiosity what Groups is Black and Gold Engine oil?

[Swiftpimp]

pretty sure there isn't a Coventry auto in Townsville Even if there was, it aint gonna be there for long! (inside info )

[MorganV8]

swiftpimp if your after some asap im moving from cairns to townsville on tuesday i could probably get u some pm me

[Swiftpimp]

cheers mate. i'll let you know. i heard autobarn sell it, so im going to drop in there and see. if not, i'll let ya know

i could always ring my old work (Coventry Autos in Nambour) and get some sent up too

[scoobygirl]

Interesting info. I've always run Royal Purple in my rexes...seems to be good stuff. I change it every 5-7K. Though mine's not exactly a race application.

Edited by scoobygirl, 10 August 2008 - 07:03 PM.

[ohbaby]

Interesting info. I've always run Royal Purple in my rexes...seems to be good stuff. I change it every 5-7K. Though mine's not exactly a race application.

How much is a bottle/container of Royal Purple, being reading about it lately and from what Ive read is sposed to be really good. .

[scoobygirl]

It's around the $80/5L mark.

[ohbaby]

It's around the $80/5L mark.

SweeT. . Have to get some lol not yet no need lol get sum at xmas

[techart]

Synthetic Oil kills Porsche engines so i'll never touch the stuff... considering my car needs 10-12L of oil i am happy to be using the proper stuff from the earth.

[Urban Monkey]

This information kindly provided by Rolls, some_cs_student, & trex101

When choosing oils the better the rating, generally the better the oil, and also the more expensive. Keep in mind even the Group II oils are probably still better then any oil that was made when your car was manufactured.

Basic explanation of ratings

Group I - mineral
Group II/II+ - hydrocrak (VI below 120)
Group III - hydrocrack (VI above 120, mineral derive "Fake Synthetic")
Group IV - polyalphaolefin (man made Synthetic)
Group V - Ester & other un-group fluid (Ester or Polyolester, super high grade Synthetic, good for aircraft jet engine).


Common products and their ratings.

Redline (Group V Polyester)
Motul 300V (Group V)
Motul 8100 E-Tech 0W40 (Group IV/V Blend)
Mobil 1 (Group IV)
Motul 8100 xcess 5w40 (Group IV) ~$59 - one of the best value
Castrol SynTec 0w30 (Group IV) [A minor mistake in the front page, Castrol SynTec 0w30, the German castrol is group IV. The American 5w40 or similar is group III (sometimes written as III/IV but not true group IV).]
Castrol Edge Sport 5w30 or 10w60 (Group III)
Motul 4100 Turbolight (Group II?)

Keep in mind that the 100% synthetic stickers mean jack, just means that the oil is at least Group III. As far as viscosity ratings go, this depends entirely on what temperature range your car is going to be used in and your driving style (track or street car) A decent read through this thread should help you answer that.

As far as oil filters go, get a genuine nissan one if you don't want to spend much, these are superior to ryco/cooper.

On Selecting Which Viscosity
There is alot of factors to consider when choosing oil weight and it's quite difficult to give you any good advice by your above description.
There are 2 major considerations in choosing oil viscosity,

1) Fuel dilution (fuel blowby into oil sump effectively thin down the oil viscosity)
Thicker oil can withstand more fuel dilution then thinner oil but thicker oil also causes friction drag, slower spool, higher FC and more startup wear.
For example: If you run Penrite Sin 25 25w60 in your engine, at 10’c morning when you first crank your engine, you would have effectively run 1131cSt startup viscosity. That’s like 4.5 time thicker then Mobil 1 0w40 (248.8cSt@10’c). It’s like running greases through your engine instead of oil.

2) Engine oil temp
Higher oil temp effectively thins the oil down.
For example: Mobil 1 0w40 is 14.3cSt @ 100'c but when avg oil temp raise to 120'c, it would have thin down to 9.1cSt which mean that it is effectively a 20wt oil (you do not want to run a 20wt oil when you racing down a track, do you). So if your avg oil temp are 90’c, any 30wt oil will do as it is effectively a 40wt oil at that temperature.

The key to the correct oil viscosity depends on mostly the above 2 conditions. There is no one size fit all oil.

Oh, IMO some brand of oil are known to withstand quite abit of fuel dilution before thinning down. Redline & German Castrol is one of them. That’s why it’s highly recommended in BITOG for track or high hp muscle car usage.

http://www.skylinesaustralia.com/forums/in...amp;qpid=481486

I myself use Fuchs Supersyn 5W-40. It's a group 4 oil on par with Mobil 1.

Edited by Econovan, 01 January 2009 - 01:32 PM.

[sinister]

Synthetic Oil kills Porsche engines so i'll never touch the stuff... considering my car needs 10-12L of oil i am happy to be using the proper stuff from the earth.

Perhaps the older ones but that is the same with any older vehicle. It's far from a Porsche only problem.

Newer engines have tighter tolerances and newer (synth) oil is typically too thin to use on older engines with larger tolerances, which is the problem.

A quick Google search and I found a wide variety of newer Porsches suggesting Mobil 1 which is 100% synthetic.

I think you'll find virtually all new cars will suggest a fully synthetic oil but if you're buying for a car 10 years or older then you'll probably want something mineral or semi synethic.

[ljxu1torana]

to get full benifits out of full synthetic oils is like touring cars 12 and 24 hour endurance races that gets revs to 8 grand all day every day. it is a waste of money putting full synthetic oil street car.

[Falconxf88]

So what would be best for my b16a and 4.1 250 crossflow turbo?

[sir355]

+1 for royal purple. expensive but worth it. $100+ a five litre bottle

[Sixes350]

Im happy with Magnatec 10W40 in the engine. Have used it in my last 3 vehicles and it performs well. I can't justify the $100+ for full syn oil every 5K.

I do use full syn oil in my gearbox and diff as they are longer lasting oils which don't need to be changed frequently.