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In terms of UOA - there is heaps of UOA posted around the net and when people change oil from one type to another the wear recorded can usually changes during that first new interval so I would say that real life examples go against your two year example. ie. both cases would show similar wear assuming a decent interval, say 5000kms. The UOA does not seem to really show what happened previously, only what happened in the last period since probably 90%+ of the oil is flushed out of the system when you do a change.

That's because there are more than a few people on the internet running with the misconception that a UOA is the ultimate in revealing how good or bad an oil is, not taking into account the thousand of other factors which affect UOA results...or the original purpose of a UOA. The bottom line is we're not all trained scientists performing double blind tests under controlled conditions, nor is the engine going to be operated under controlled/consistent conditions - worse than not doing a test at all, is doing it incorrectly and misdiagnosis. A UOA is useful for one person, using the same oil consistently, monitoring the wear of their engine - that's what UOAs were originally designed for. Even then the results are only indicative.

So, bad oil...or:

- Wear of other filters in the engine

- Hard/soft driving

- Changes to driving distances

- Engine startup frequency

- Engine running time

- Lack of vehicle use

- Time difference between test intervals

- Bad batch of fuel resulting in detonation

- More/less oil put in than last time, diluting/concentrating results

- Climate: hot/cold weather altering first start and engine shut off wear

- Oil drain process: contaminants left behind in engine

- Oil drain process: previous oil left behind in engine

- Oil drain process: engine flush removing protective carbon buildup and possibly inducing more engine wear with the fresh oil

- New oil removing more contaminants from engine offering the misperception it is causing them

- Bad batch of oil

These are just off the top of my head...and I'm no scientist. There's a hundred factors involved in it, all with their own little impact on UOA results. The beauty of human touch is that it carries an infinite sense in terms of perceptability. That's why a mechanic will test drive a vehicle to diagnose and resolve a problem - we don't go measuring each and every part on the vehicle to see if it's still as factory / the extent of wear on it - then when that checks out fine, say "she's all fine despite that horrible noise you can still hear". That's why I'd rather drive my car and use my senses to tell whether the oil I've put in it is making it run like a pile of shit or the best it's ever run before. But each to their own...

A UOA only tells you what's happening on a molecular level. Real world experience of driving the car, feeling how it's running is more important in my book. A UOA could tell us a 10w70 margarine oil is the best because it has no shear and maintains it's viscosity over time. A real world analysis of this would tell you within seconds, WTF did I just put in my engine!?

First you need to find an oil that's the right weight, then based on what you want to spend whether it be mineral, poly or ester based. Only then once you've tried the oil out, driven the car and are happy with how it's performing is a UOA of any benefit. As it's the length of time you use an oil that then makes a UOA relevant. In this case, it would make a case if we ran Sougi for 10,000kms vs 5000kms or 7500kms. Then we could see the oil doesn't sheer until X kms, thus we can safely get 10,000kms out of it, or to be safe change it at 8000 or 9000 etc.

An analysis of used oil is a waste of time without factoring how your car responds to using it in the first place.

Correcto!

I'll flat out admit that I hate UOAs. They are overrated and overused as a means to diagnose the effectiveness of an engine oil...too many underlying factors are involved. They are actually more useful in determining if there are other problems with the engine, or whether the oil is in need of a change, rather than the effectiveness of an oil in the first place.

Went and bought some more Sougi s600 from the distributor on the gold coast yesterday and was asking him about the situation on the cease of manufacturing of this product.He rang GW headquarters while i was ther and asked them a few questions.

1.Are they still making s6000? They replied :no

2.What do they offer as an alternative:Syn x 3000

3.How would it compare to s6000 as it is only a group3 :They put us through to the chemist for this one and he fully believes

that it is every bit as good if not better than the s6000 because of the additives.Although it does not have the esters they have put other stuff in that does as good a job.He also pointed out that the syn x is an SM classed oil and s6000 is only an SL.

So after all that i still purchased 2 bottles of S6000 as im still pretty sceptical about using a group 3.Damn frustrated and confused.

Went and bought some more Sougi s600 from the distributor on the gold coast yesterday and was asking him about the situation on the cease of manufacturing of this product.He rang GW headquarters while i was ther and asked them a few questions.

1.Are they still making s6000? They replied :no

2.What do they offer as an alternative:Syn x 3000

3.How would it compare to s6000 as it is only a group3 :They put us through to the chemist for this one and he fully believes

that it is every bit as good if not better than the s6000 because of the additives.Although it does not have the esters they have put other stuff in that does as good a job.He also pointed out that the syn x is an SM classed oil and s6000 is only an SL.

So after all that i still purchased 2 bottles of S6000 as im still pretty sceptical about using a group 3.Damn frustrated and confused.

Birds has mentioned Syn X 3000 before. It's apparently pretty good oil. I think the chemist who told you it was better than S6000 doesn't know his own product. S6000 is also full of additives, or didn't he know that. Probably not by the sounds of things lol. I think Birds will chime in on what he thinks of this, but I doubt Syn X is "better" than Sougi.

Anyway, Birds has mentioned GW (Andrew) was reconsidering the plan to cancel production of Sougi. I'm not sure if who you spoke with now has the most up to date news, or whether it's still in the "reconsidering" phase.

You did the right thing in buying Sougi. It's a group 5 oil, and I don't care how many additives are in the Syn X, it's still group 3. Common sense tells you a company would not be putting in better additives into a lesser grade oil, that's cheaper and then saying it's as good if not better. It's not crap, I'm sure of that, but it's not better is what I'm trying to say. Very good chance the same additives in Syn X are also in Sougi, but more likely Sougi has better quality additives, and a greater volume of them vs Syn X.

looking at the different bases from a chemical perspective, cracked mineral oil is quite different from esters. that would influence the additives and their concentrations that can be mixed into the oil to get the right weights. just a thought

Yes GW have stopped making S6000 for now, i.e. they aren't blending any more for now (though they still have heaps of bottles in stock), so there's no denying that...ultimate proof came when they sent me an updated distributor price list and Sougi had been removed from the list. What I meant by reconsideration to cancel Sougi is that they may make another batch of the stuff in future (remember each batch is several thousand litres at a time, hence it was causing storage problems to maintain this slow moving product line). Andrew told me if they get enough of a response to it then they will produce another batch once the current one has been depleted.

Syn-X 3000 (10w40) is a very good oil...it's my biggest seller because it's very cheap (talking a couple of cents a litle more than GW's mineral 15w40) and is very versatile when servicing a range of vehicles. The mechanics love it. I imagine it would run fairly well in a Skyline based on viscosity alone, but haven't tried it yet. GW's chemist would know much more about it than me, afterall he makes the oil...and he's correct, it does meet a more updated API specification (SM) than S6000 (SL). To be honest I'm glad to hear that...it's nice to know there could be an oil on par with Sougi in terms of performance for less than half the price (even if it's not fully synthetic).

The issue we have is that we love our ester based oils, emotionally so too...and obviously your service interval is going to be shorter than using fully synthetic S6000. But hey, prove him right/wrong and give Syn-X 3000 a shot maybe...if it works as well as Sougi does then you save even more money on buying the 300V lol. Might try Syn-X on my next oil change and let you know how I go. So far Sougi M5000 has been great, felt fantastic putting it through the high revving motions at DECA yesterday.

Yes GW have stopped making S6000 for now, i.e. they aren't blending any more for now (though they still have heaps of bottles in stock), so there's no denying that...ultimate proof came when they sent me an updated distributor price list and Sougi had been removed from the list. What I meant by reconsideration to cancel Sougi is that they may make another batch of the stuff in future (remember each batch is several thousand litres at a time, hence it was causing storage problems to maintain this slow moving product line). Andrew told me if they get enough of a response to it then they will produce another batch once the current one has been depleted.

Syn-X 3000 (10w40) is a very good oil...it's my biggest seller because it's very cheap (talking a couple of cents a litle more than GW's mineral 15w40) and is very versatile when servicing a range of vehicles. The mechanics love it. I imagine it would run fairly well in a Skyline based on viscosity alone, but haven't tried it yet. GW's chemist would know much more about it than me, afterall he makes the oil...and he's correct, it does meet a more updated API specification (SM) than S6000 (SL). To be honest I'm glad to hear that...it's nice to know there could be an oil on par with Sougi in terms of performance for less than half the price (even if it's not fully synthetic).

The issue we have is that we love our ester based oils, emotionally so too...and obviously your service interval is going to be shorter than using fully synthetic S6000. But hey, prove him right/wrong and give Syn-X 3000 a shot maybe...if it works as well as Sougi does then you save even more money on buying the 300V lol. Might try Syn-X on my next oil change and let you know how I go. So far Sougi M5000 has been great, felt fantastic putting it through the high revving motions at DECA yesterday.

Awww man that's bad news after all. The problem Andrew has to realise is it's not so easy to just get everyone back on board if they do decide to make another batch. If the supply to the end users (old computer term lol), meaning our supply of being able to go buy some Sougi doesn't stop, then it doesn't matter if they havn't made any as we won't feel the effects. But if it stops what's going to happen is people will find alternatives and quite possibly won't come back to using Sougi. Thus it's a chicken vs the egg thing in that demand will decrease due to people not being able to buy it.

Regardless of Syn X, I want to keep using Sougi. So if Motul ever make a 8100 in 10w40 that's probably my first choice to try that. Other than that, all I can do is save up and try to stockpile some of the stuff as I'm not sure what Andrew is thinking if demand changes to then persuade them to keep making it. I would think the fact alot of us have or are planning to go down and buy 4-5 bottles of the stuff, should be proof to keep it in production in the first place.

Well, by all means do your best to keep Sougi up and running, I know I will. I have dibs on the last of it so I will certainly be stockpiling. Don't forget about M5000 too...you'll be able to stockpile twice as much of this one (nearly half the cost) and IMO it's as good as S6000 minus the extended service interval.

hey birds. sold the gtr. now I have to got through this whole process again for the 08 wrx. It is suggested by subaru to use a castrol 10-30, but that sounds very thin and I dont trust castrol. I was going to stick with the motul 300v 10-40. What are your thoughts?

Did the dealer suggest that to you personally or is that in the user manual as a recommended oil? How many KM has the car done? I'm not familiar with the engine, it may have tight tolerances...10w40 should be fine in it, maybe give this a shot and see how it compares to the 10w30...you won't do it any harm for one service interval.

I had a Mazda Tribute at the workshop the other day that had 5w20 on the oil cap...! This engine DID need a thin oil though, very tight tolerances. We only just got away with putting a 30 in it...

wow, 5w20 for a tribute lol. Who would have thought. The car has done 30,000 and the salesman at subaru said the service centres use a magnatec oil and is 10w30, or was it 5w30. Something like that. How would I go about finding out a cars tolerences?

wow, 5w20 for a tribute lol. Who would have thought. The car has done 30,000 and the salesman at subaru said the service centres use a magnatec oil and is 10w30, or was it 5w30. Something like that. How would I go about finding out a cars tolerences?

Stick to the manufacturer spec or slightly thicker, its not just the tolerances you need to worry about so I wouldnt worry about trying to find out. 300v comes in 5w-30 so if you can get a hold of that it would be pretty safe to assume its some of the best oil you can use for your car assuming hard use.

Agreed Redline is the top if the group V oils for a reason. It last for ages and it work in any engine in all conditions environmentally and engine wear. I agree that the choice of oil and performance comes down to a road test but Redline, without a problem wether it ge the engine or gear oils will always improve a car in some way.

E.G my car has only 7000km and after the first 2000km of it beding in the oil already makes the engine more free flowing resulting in a more powerful feeling-responsive engine in the cold mornings, so its even showing positives on a re-build street tuned engine.

Only thing i would see people not buying and saying fair enough use a different oil ..... would be because of retail price.

hey birds. sold the gtr. now I have to got through this whole process again for the 08 wrx. It is suggested by subaru to use a castrol 10-30, but that sounds very thin and I dont trust castrol. I was going to stick with the motul 300v 10-40. What are your thoughts?

I've had a couple of WRXs both 00s and I found they were happiest on 15x50 but both were 2ltr and both had over 90000ks on them, the 08 will be the 2.5ltr and there were plenty of not nice things with that size in the early days particularly the US ones, give a search or two on REXNET theres heaps of good stuff on oils .

not nice? that doesnt sound...nice. I would think/hope that with the 08-10 versions they would have made a decent setup. I did some searches on REXNET. Not a bad forum, I prefer SAU with the stickies. REXNET dont really have an oil dedicated thread, just some random mentions here and there. Unless I suck at searching lol.

scratch that, dug a little deaper and found their 10 page oil thread. Thay have not really come to a proper conclusion, nor have they made any mention on the new 2.5ltrs. I wonder if it is the same engine as the forester, except with a TD04? Might call the service centre and have a chat with them. Thanks for your help Birds, BASHO, siksII and central coast person lol.

I heard that a while back when the 2.0 WRX was out Subaru was recommending a thin oil as standard... A lot of new cars from around NT/WA that had high speed/high temperature use spun bearings in a short period.

I have no reference for this but a good friend of mine at the time that had one mentioned it.. people started to use a heavier oil than standard to avoid that. I doubt its the same with the 2.5 being a new motor but food for thought anyhow.

not nice? that doesnt sound...nice. I would think/hope that with the 08-10 versions they would have made a decent setup. I did some searches on REXNET. Not a bad forum, I prefer SAU with the stickies. REXNET dont really have an oil dedicated thread, just some random mentions here and there. Unless I suck at searching lol.

the early 2.5's tended to blow head gaskets

like my outback did :thumbsup:

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