StudentScooby

mine has always been run on 15w50 silkolene pro s never had a problem so wouldnt take the risk of changing it now.

Setright

Right! I have been reading this entire thread, quite thouroughly:

I agree with the following:

1) People make oil choices with too little knowledge and too little information. "My mate says this is good" is too often heard.

2) Oil flow is an important factor in oil-choice. And people in this thread, reducing that theory to thinnest being best are missing the point - even the Captain. As with so many other things in life, extreme ends of the scales aren't the way to eternal happiness. No...finding the sweetspot inbetween is the correct choice.

3) The oil recommend in the owners manual is a compromise. And therefore shouldn't be defended so vehemently in this thread/forum, where we all seak the optimum solution...not compromises. That's why we own Subaru's, right?


I disagree with:


1) Oil that could be as thin at start-up, as it is at op temp would be the best ever. NO! NO! NO!
Why? Because the metals that the engine are made of, expand as they are heated. The spaces within the engine will change from cold to hot.

I am sorry Captain, but your failure to make that point, make it so hard for me to support you. I really want to, because you do make some good points, but forgetting the effect that heat has on metals....what else did you overlook??

captain_anonymous_2003

Quote:

Originally Posted by Setright

Right! I have been reading this entire thread, quite thouroughly:

I agree with the following:

1) People make oil choices with too little knowledge and too little information. "My mate says this is good" is too often heard.

2) Oil flow is an important factor in oil-choice. And people in this thread, reducing that theory to thinnest being best are missing the point - even the Captain. As with so many other things in life, extreme ends of the scales aren't the way to eternal happiness. No...finding the sweetspot inbetween is the correct choice.

3) The oil recommend in the owners manual is a compromise. And therefore shouldn't be defended so vehemently in this thread/forum, where we all seak the optimum solution...not compromises. That's why we own Subaru's, right?

Correct, correct (but saying I have not covered this is incorrect I am afraid see the following) and correct...

I think you'll find I have always suggested that you should select an oil based on your operating conditions. And most that have read this will have hopefully had that point drilled home! So suggesting in point 2 I have missed the point, is incorrect.

Quote:

Originally Posted by Setright

I disagree with:


1) Oil that could be as thin at start-up, as it is at op temp would be the best ever. NO! NO! NO!
Why? Because the metals that the engine are made of, expand as they are heated. The spaces within the engine will change from cold to hot.

I am sorry Captain, but your failure to make that point, make it so hard for me to support you. I really want to, because you do make some good points, but forgetting the effect that heat has on metals....what else did you overlook??

Incorrect, I refer you to the following:

"I thought everyone knew that 90 percent of engine wear occurs during the startup period because oil is just too thick. Some think it is good to have a thicker oil for startup since the parts shrink when cold and would otherwise “rattle.” Sure, your piston diameter will shrink on cooling but so will the diameter of your bore. The net result is about the same clearance hot and cold. This is not true for your valves. They lengthen when extremely hot. In the Murcielago they use shims instead of self adjusting valve tappets. You need to put a millimeter of clearance there so that after expansion the valve will not be held partly open when it is supposed to be closed."

"The manufacturers know what parts shrink or expand and the clearance changes that result. You do not have to worry about this. If it was that easy to design engines we would all be making them."

Manufacturers place very close attention on metal selection and the expansion and contraction of those parts as the engine warms up. This is something that is extremely carefully designed. If they didn't pay attention to this pistons in cylinders could be flapping about. This is of course not true at all. What you are saying here in point 1 of your disagreements is not correct. I hope I've illustrated why and this helps you understand.

One other thing, and I know some of you will be horrified, but there is nothing particularly special about a Subaru engine that makes the oil choice so much more critical than say the choice of oil in an another make of car.

captain_anonymous_2003

Have you ever had an analysis? If not how do you know your engine wear is reasonable? Simply because you've not had a problem up to now isn't a good test of an oil. You could use and oil totally inappropriate for your needs for a long time until the effects of its use are noticable.

TonyBurns

iTrader: (3)

Ignorance is bliss

I would run a 0w30 in my astra diesel with no problems, I wouldnt run it in my subaru petrol 2ltr turbo though, though the subaru diesel may be a different issue as thats a newly designed unit (from scratch).

Ever heard of "the exception to the rules?" You now see it in this subaru engine

Tony

captain_anonymous_2003

I wouldn't advocate this either. I think I've already said this many times. I'd probably go 10W-50 or 15W-50 for a car that is tracked regularly.

Sabas

iTrader: (22)

Craig, I think a little more info on UFO's is needed, not UFO's, Uoa's, what they do and where to send the oil, and maybe let us know the results of yours when you send it off and get them back

captain_anonymous_2003

It's not ignorance, and again at no point did I suggest using a 0W-30. Why is it you are making out I've made recommendations when I have not. Stop trying to discredit me by making out I've made recommendations when I haven't. I hope everyone reading this post will take that point too and realise your arguments are flawed, and your tactics to discredit what I am saying are somewhat underhand.

I've said this over and over. As far as I am aware your disagreement with me is the use of 0W oils and yet you keep shifting about to other topics randomly. I believe a 0W oil is perfectly fine, and I have explained why. You have not provided one shred of evidence to support your claim that it is not. Please stick to topic.

If you'd like me to further clarify for you. There is nothing so blue sky in an Subaru engine that makes a 0W oil totally unsuitable.

captain_anonymous_2003

UFOs! You're on the wrong forum my friend! lol

TonyBurns

iTrader: (3)

Buy a turbocharged subaru and run what you want in it Its even been said by a very reputable engine builder that this is a very fussy engine when it comes down to oil, it doesnt like 0w ones its as simple as that, its not a perfect world, it never will be, there will always be exceptions to the rules, there always will be, your not listening and we own these cars, you keep saying 0w, we keep saying
Like I said, I would quite happily run a 0w in my diesel, just not in my subaru

Tony

captain_anonymous_2003

Reputable engine builder... Saying things like this doesn't win the argument Tony I am sorry... A reputable engine builder should know better than to blanket recommend an oil viscosity to everyone without understanding their needs surely!? If they're recommending 15W-50 then I suggest it's due to the following:

1 - They've made an assumption that since the engine is probably highly tuned the end user will drive hard and potentially track the vehicle rather than use is as an every day commute. (probably more likely)

or

2 - They don't understand oil and are simply making that recommendation because 'that's what we've always done'.

Seriously this is getting dull now. It's obvious you don't know much about this subject, but I bet you reacon something.. Why not write another post on this forum titled "What I reacon".

(M&W credit there)

Jolly Green Monster

iTrader: (4)

your still not getting it captain

TonyBurns

iTrader: (3)

How about "Your just ignorant?"
He even said in a perfect world it could happily run 0w oils..... oh well, as you dont own the car(s) we are talking about then you dont know the quirks that go with them
Go browse elsewhere, actually just go trade your M5 in and get a subaru, do what the hell you like with that run it on 0w30, 0w40, 0w50, I dont care, you will though when it starts knocking, and dont say we didnt warn you, 0w oils dont go well with this engine (again).

Tony

PS, if I said that the Vanos system is the most infalible system ever built by BMW, never has any problems, would you agree with me?

TonyBurns

iTrader: (3)

You even wanted proof, what more do you require

captain_anonymous_2003

Tony and Jolly,

Both of you have continuously failed to support your dogmatic views with regards to oil. I find it truly horrifying that you made the 15W-50 suggestion to Dave Jolly, it's absurd frankly and clearly demonstrates your complete ignorance on this subject. You then made a totally ridiculous remark which I debunked in about a second and despite this you didn't stop and think about it or acknowledge it you just ignored it. That is the very definition of a dogmatic view. That is a shame too as what you both say continously flies in the face of fact. There has not been one shred of evidence to support your views and yet I have presented reems of it to support mine. I think 99% of those that have read what I wrote would agree.

All,

I am finished with this thread now I will no longer reply, it's descended into something pointless.

You have two choices. You can either give in and listen to dogma, and just go along with what people like Tony reacon (despite it being founded on nothing at all). Or you can actually find out for yourselves using £30 analysis and the reems of literature on the subject (all of which support what I have said all along btw) and a reputable expert oil supplier like Tim. I have absolutely no personal or vested interest in your choice of oil, I don't really mind what you use. My main point which I have maintained so far is that your oil choice should reflect your needs and blanket recommendations are often unconsidered without that information. Don't be frightened of 0W's, I hope you can see they stand up to the unfounded and illogical scrutiny put forward here and there are benefits to their use which might come into play for you.

And I know what will happen now; typically after I stop replying Tony and anyone will chime in with how stupid I am. That will be a true testament to their character and should also be taken into account when considering their 'views'. I like a forum where learning is encouraged and a difference of opinion is explored through constructive and informed discussion, this thread unfortunately hasn't been place like that, I hope others are different. It makes me wonder how much more bad advice and dogma exists here that new owners fall foul of every day. Listen to what people have to say, consider it, but don't blindly follow unless you are sure you understand and have considered the facts.

If you wish to ask me anything feel free to PM me, I'll always do my best to answer.

Thanks for reading and cheerio

Craig

Maz

iTrader: (34)

Don't be put off by this differing of views, this is Scoobynet after all. You've certainly given people food for thought. Just because someone is shouting louder than you doesn't make them right.

TonyBurns

iTrader: (3)

Ah get the last word in, will wave goodbye to you, wish you the best in the future Craig, hope you have a nice time on the other forums, but do your homework first, we all understand about picking for the right situation, its just you keep throwing 0w oil at us, and we keep saying, not in this engine, yet you point blank refused to listen, we said yes, any other, just not this one, you refused to listen.... oh well and Bon Voyage.

Tony

PS, go have a chat with that guy, tell him us stubborn subaru owners wont change our ways

Setright

Fair play, if I missed that.

I must say, you seem to have dug yourself in deeper, though Captain. Steel crankshaft, alloy block....alloy pistons, in a steel liner.....those aren't likely to have the same expansion characteristics.


(And before anyone starts saying the crankshaft is cast iron, not steel, please refer to page 1 of your metallurgy book: Iron, with carbon added, is steel.)


Oh, Captain, you suggest that water could be a good lubricant because it's so very "thin"....that's what I am refering to in my second point.

TonyBurns

iTrader: (3)

Set, a couple of microns of oil can protect, just not protect that well if you have no flow
Still the main link is interesting, lots of good information there but then some silly bits like draining your car and leaving it, filling it up and hoping that its going to be ok when you start it, its extremely noisy for 10 secs (metal on metal, would hate to see the damage ) then goes quiet (As Paul said, you cant do that on a subaru), 2 secs of oil starvation would kill it

Tony

gallois

This is what i have learned so far:

15w-50 is far more shear stable at HIGH TEMPS than say a 5w-50, meaning it will stay at a 50 weight for longer. Cold start protection suffers, not so much bearing surfaces, which rely on pressure, and the pump can cope with 85psi of pressure, but splash lubricated components.

The ONLY downside to a 0w oil is the VI improvers needed to make it perform as a 0w cold, and a 40 or 50 hot can make it more unstable, i.e. it could shear down quicker than a 10w but this is only proved by carrying out an oil analyisis.

The weight of oil you use depends on the oil temperature you run at, if your oil exceeds 100deg by some margin, then it thins out beyond what subaru want, and pressure drops.

Correct oil pressure is the most important thing.



If i were to recommend an oil, then it would be what subaru themselves recommend. If the car is not standard, then i would recommend an ACCURATE oil temp and oil pressure gauge is fitted as part of the modifications, and then are the temps within what subaru designed them to be? i.e.

80deg at sump, if so, then use what subaru want you to use, go one grade higher if you regularlyy give it some, watch your pressure, 14psi at idle hot, 43psi at 5000rpm hot is what subaru specify (from what i have found),

if your pressures are higher than this, then your oil is too thick, lower than this and it is too thin.

What is the downside to pressures going higher than what subaru want? Well apart from a decrease in economy, and localised overheating of the oil due to drag (which will shear it down prematurely, more so on an oil with a wide viscosity i.e. 5w-50 compared to 15w50), not much, as the oil is still forced through the engine at the same rate, go silly thick though and some passively splash lubricated components could suffer due to the thicker viscosity , and the actual oil pump will bypass at around 85psi, so is good for 85psi, whether it will live for long constantly at his pressure is another thing though.


Based on this, my choice of oil (until i get an accurate pressure gauge) will be an ester based (due to superior shear stability and clingyness) 5w-40. probably millers CFS.

i have found a few companies in the UK that will carry out a Used Oil Analysis, prices are around £30, google will find them, heres one though. http://www.theoillab.co.uk/

Speccy D

Just to stir things up, I was able to drag captain anonymous away from his PC for a short period yesterday and took him for a spin in my modded bugeye STi. He even had a drive and, after recovering from the initial upset of realising it was faster than his M5, he actually liked it!

We shan't mention what oil was in it...

joz8968

iTrader: (13)

LOL! ^^^

# wa wa waaaaa #

Speccy D

Sorry craig that was mean of me but I couldn't resist. I should have said "slightly faster" and it was 5w40 btw

TonyBurns

iTrader: (3)

5w40 is one of the best oils you can get for you standard(ish) scoob, now a fact you probably didnt know (well the old farts on here will ) is that Mobil 1 back in the late 90's did a 5w40 fully synthetic just for Subaru UK as there was no other oil that was suitable for this car in a fully synth with a 5w, of course if people would have asked, they may have gotten an answer (ive know that fact for 10 years )

Tony

joz8968

iTrader: (13)

If we were to act on captain anonymous 2003's info, then when the EJ motor is crying enough's enough, are we therefore allowed to bellow at him, "She's aboot tooo blooow, cap'ain!!!"?

his-n-her-scoobs

iTrader: (5)

Not 15W50 then LOL

oilman

iTrader: (9)

It's simple really, all cars are different and used differently. Scoobynet is no exception.

Ask the OIL experts, it couldn't be simpler......

You'll get GUY or TIM's recommendation based on your spec/use here:

http://www.opieoils.co.uk/frmRecommendAnOil.aspx

It's FREE and GOOD advice based on many owners and customers!

Cheers
The OPIEOILS Team

neil1980

iTrader: (2)

well i use 10,40 magnatec always have always will in all my cars from my astra mk3gsi to gsi turbo to my pug diesel to my scoob never had a ounce of a problem

ZEN Performance

Then perhaps you should be more clear about what you post.

JohnD

iTrader: (5)

And of course, before they replaced it with the 0/40, Mobil 1 was 5/50 (the perfect compromise grade?) Back in the early/mid '90's it was the oil of choice by the Cosworth and RS Turbo boys.
Millers list a 5/50 full synth. Unfortunately it's not in their CFS range

JohnD