Costs of synthetics vary considerably. The most expensive are the “Ester” types originally only used in jet engines. These cost 6 to 10 times more than high quality mineral oils.

The cheapest synthetics are not really synthetic at all, they are dug out of the ground and not manmade. These are in fact specially refined light viscosity mineral oils known as “hydrocracked” oils.

“Hydrocracked” oils have some advantages over their equivalent mineral oils, particularly in lower viscosity motor oils such as 5w-30 and 5w-40 and they cost about 1.5 times more than good quality mineral fractions. This is the “synthetic” which is always used in cheap oils that are labelled “synthetic”.

So, why are these special mineral oils called “synthetic”?

Well, it all came about from a legal battle that took place in the USA more than ten years ago. Sound reasons (including evidence from a Nobel Prize winning chemist) were disregarded and the final ruling was that certain mineral bases that had undergone extra chemical treatments could be called “synthetic”.

Needless to say, the marketing executives wet their knickers with pure delight! They realised that this meant, and still does, that the critical buzz-word “synthetic” could be printed on a can of cheap oil provided that the contents included some “hydrocracked” mineral oil, at a cost of quite literally a few pence.

So, the chemistry of “synthetics” is complex and so is the politics. The economics are very simple though.

If you like the look of a smart well-marketed can with “synthetic” printed on it, fair enough, it will not cost you a lot; and now you know why this is the case, it’s really only a highly processed mineral oil.

But, if you drive a high performance or modified car, and you intend to keep it for several years, and maybe do the odd “track day” or “1/4 mile”, then you need a genuine Ester/PAO (Poly Alpha Olefin) synthetic oil.

These oils cost more money to buy, because they cost a lot more money to make.

Very simply, you always get what you pay for, cheap oils contain cheap ingredients, what did you expect!

Good thread

Edited 24 May, 200719 yr by Mike_Rigby

^^^agreed^^^

you learn something new every day

I knew about the cheap ungraded oils (ie ones without an SAE number on them) but I didn't know about that...

So you can put any oil in any car, and what about filters? I want to start changing oil and filter myself and have no clue.

Very informative, Oilman. Is there a way of telling them apart, other than the price, some labelling on the jug?

if you look on the back of the bottle to you will notice a pair of letters,

the higher the pair of letters the better the oil

so if you see sumin lik AA then its shite were as zz is the best but doesnt exist. lol

i think they average round about CC CD CE or sumin lik that

a bloke from miller oils told me that

Edited 4 June, 200719 yr by 97polo_16v

I agree with what you say about you get what you pay for, however, I will say this much. If you have an older say 8v car, it may be better to use a non synthetic oil with a higher SAE number. This may help if you have problems with smoke from say your valve stem seals or the like.

A lot of guys I know have been stung by the promise of longer engine life with those so called synthetics, especially in the higher mileage multi valve engines, only to find that after even only a short time, they have begun to smoke quite badly. Some of them thought, and rightly so, that they had a major problem and carried out a strip down and rebuild, sometimes at the cost of hundreds of pounds. Others thought a bit longer and decided to go back to mineral thicker viscosity oil and lo and behold, no smoking, no weeping gaskets etc. OK I know it's kinda masking a problem, but valve stem seals and weeping gaskets is not going to stop you from driving, especially if you keep a close eye on your oil level.

Personally, in my other car (a big old V*****ll) I change the oil and filter every 3000 miles, and I use cheapy supermarket oil as well. When I got her at approx 92k, she wept from just about every gasket, (she had Vx own semi synthetic at her previous service) since I have had her, done 25k in 3 years, many oil changes, abiout 8 IIRC and last time I looked, she was dry as a bone underneath. All I'm trying to say is, you can use cheap oil as long as you change it regularly.

JM2pW and I am not a mechanic by the way

Jon

G40 Jez and 97polo 16v, this thread might help explain things a bit better: http://www.clubpolo.co.uk/forum/index.php?showtopic=67007

I partially agree with bootie3367. Don't automatically assume that synthetic oil is always the best choice, especially when these oils tend to be 'thin' grades like 0w/30 and 5w/30 for example. Viscosity is still important. In basic terms, just obey what your handbook recommends as far as viscosity and quality goes and you'll be fine. The latter won't be as relevant when the car is older, as quality improves and the grades in the handbook become obsolete. The frequency of changes is just as important as the quality of the oil.

As far as the 'you get what you pay for' mantra is concerned, I’d say what oilman says about fully synths sounds very logical. However, with more 'normal' oils I think it's a bit of a grey area. Going for the most expensive 10w/40 semi, for example, won’t guarantee it’s better than its lower priced rivals. The slightly pricy Magnatec being a common example. It's nearly twice the price of identically specced alternatives. Also, shop around, as many retailers can sell the same oil at significantly different prices. I'm no expert on oils though, so no-doubt oilman can clear up any errors.

So you can put any oil in any car, and what about filters? I want to start changing oil and filter myself and have no clue.

No you cant, your hand book will always point you in the right direction though. A filter change with every oil change is all you need and ideal.

Cheers

Guy.

Very informative, Oilman. Is there a way of telling them apart, other than the price, some labelling on the jug?

Sadly no there isnt, buzz words like "technosynthese" "synthetic Technology" etc all tend to mean hydrocracked mineral oils. Ester based oils are often advertised as such, they cost a lot to make and do stand out from the crowd in terms of quality so the oil companies like people to know they sell one.

Cheers

Guy.

I agree with what you say about you get what you pay for, however, I will say this much. If you have an older say 8v car, it may be better to use a non synthetic oil with a higher SAE number. This may help if you have problems with smoke from say your valve stem seals or the like.

A lot of guys I know have been stung by the promise of longer engine life with those so called synthetics, especially in the higher mileage multi valve engines, only to find that after even only a short time, they have begun to smoke quite badly. Some of them thought, and rightly so, that they had a major problem and carried out a strip down and rebuild, sometimes at the cost of hundreds of pounds. Others thought a bit longer and decided to go back to mineral thicker viscosity oil and lo and behold, no smoking, no weeping gaskets etc. OK I know it's kinda masking a problem, but valve stem seals and weeping gaskets is not going to stop you from driving, especially if you keep a close eye on your oil level.

Personally, in my other car (a big old V*****ll) I change the oil and filter every 3000 miles, and I use cheapy supermarket oil as well. When I got her at approx 92k, she wept from just about every gasket, (she had Vx own semi synthetic at her previous service) since I have had her, done 25k in 3 years, many oil changes, abiout 8 IIRC and last time I looked, she was dry as a bone underneath. All I'm trying to say is, you can use cheap oil as long as you change it regularly.

JM2pW and I am not a mechanic by the way

Jon

Jon,

This is not uncommon and a good way to stem oil usage, leaks and smoke. However synthetics come in all the same viscosities as mineral oils, and more so if someone wants to move to a thicker oil for one of the stated reasons they still can keep to synthetic if they wish.

Cheers

Guy.

very informative but does anyone no where i can get some of this high quality performance oil from

I change my oil and filter at 3000-4000 miles as well. Bought a 50L drum of Comma Eurolite for less than £40 so I can't complain!

very informative but does anyone no where i can get some of this high quality performance oil from

http://www.opieoils.co.uk

nice bit of info there matey.

Indeed. And no part of engine maintenance is as important as the oil. The grade of oil is still by far the most important factor - though cheap oils burn at a lower temperature,and so need more regular changes.

What type of oil is best suited for the NZ engine.

IE 10/40

ect

i use shell 10/40 API SL/CF, ACEA A3/B3

got some Halfrauds stuff exactly the same code above and it seems thinner, whats the reason for this.

Edited 16 September, 200719 yr by Messydan

Oh FFS

Yes, hydrocracked base oils are derived from mineral oils. However, for good reasons that were considered during the above-mentioned legal battle, they were considered to be so far removed from their starting point that they were effectively synthetic. Legal decisions are not made on a whim.

In terms of composition and performance, hydrocracked (known as group 3) base oils are closer to PAOs (group 4) than they are to minerals (groups 1 and 2). This is because they have undergone so much chemical treatment and alteration that they look nothing like their starting feedstocks.

A well-formulated, correctly-specified oil with group 3 base oils is perfectly adequate for most on-road uses, even in high speed use.

As for the terms "fully synthetic" and "semi-synthetic" - these bear no relation to the type of synthetic oil used. A fully-synthetic oil must be blended in base oils that are 100% group 3 and/or 4. Esters are also synthetic but sit in a catch-all called "group 5" which is defined as "anything not in groups 1 to 4", so includes natural and synthetic-derived oils so can't be generically terms "synthetic". Esters can be included in the "synthetic" portion of an oil though.

Semi/part synthetic oils contain some portion of groups 3 or 4 (or ester) mixed with some group 1 and/or 2. There are no industry rules about how much synthetic must be present, but typically it'll be >10%. These oils, if well-formulated and specified, are also very good and perfectly OK for most typical on-road applications.

Now consider this - oilman runs an oil distribution and sales company, specialises in offering synthetic options, hasn't been on here for ages and is suddenly here with a few posts in quick succession offering 10% discounts, re-posting his "oil labelling" thread (this was removed by the mods as it's already a sticky in the engine board) and now extoling the virtues of synthetics. Looks like marketing to me, wrapped in compelling but biased factual discussion.

I'm not trying to combust sales (see what I did there?)

But would like to make fellow dubbers aware, and I hope it causes no offence :-)

Sukhi.

What a stupid argument.

Looked at my website lately?

I sell everthing from Mineral oils to race synthetics, oils for classic cars and bikes (monogrades) to the latest all singing and dancing VW, BMW spec oils!

Take a look!

http://www.opieoils.co.uk

I don't care what I sell, it makes no difference to me but you cannot beat quality when it comes to looking after your pride and joy.......................Your car, money and choice!

Cheers

Simon

What type of oil is best suited for the NZ engine.

IE 10/40

ect

i use shell 10/40 API SL/CF, ACEA A3/B3

got some Halfrauds stuff exactly the same code above and it seems thinner, whats the reason for this.

What year is the car?

Cheers

1991/92

Ta

1991/92

Ta

10w-40 semi-synthetic would be my recommendation

Cheers

Thats kinda what i thought but i thought id ask the man in the know.

Thank you..