Some Good Oil Advice For You !!!

JazzyG

Dreamscience
Hi Guys and Gals ,

Having communicated with the Oilman on a previous thread I decided to dedicate a couple of days to investigating what actually is the best oil for us lot.

To my surprise I found a link on the Castrol website endorsing Castrol RS 0W-40 as VW503.01 compliant !!! Which I was told it was not , see link below
http://www.castrol.com/liveassets/b...ds/a/AU_Castrol_Formula_R_Synthetic_0W_40.pdf

I also researched into Shell , Mobil , Silkoline , Motul , Fuchs and Castrol.
After much comparison of Viscosity , Flash Points " The temp the oil could burn " , pour temperatures , Viscosity Indexes and much more ,

Basically , forgetting additives and friction reducers etc
Mobil 1 is the best Fully Synthetic Oil on paper with the highest tollerances while far surpassing the VW 503.01 index. See below
http://www.opieoils.co.uk/TechSpecs/Mobil and Motul/Mobil 1 0w-40.pdf

Hope this helps some of you out

Jazzy G
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Fishy

Active Member
May 16, 2005
1,080
4
The only time I would run an oil that is rated at 0-30 or 0-40 is to run an engine in!

The stuff is like water! and to thin even for our colder climate. Anything with a turbo should run at least a 5-40 or better even higher.

Fish
 

warren_cox

Back from the dead
I was under the impression that a "0w" oil would be acceptable as it enables the oil to get to all the vital parts more quickly thus reducing wear. I appreciate the 20vT isn't the most high tech engine but as long as its not blowing it all out the back it should be OK. I wouldn't put "0w" oil in an old worn engine.
 

Pabs

Active Member
May 3, 2004
5,936
4
Basingstoke
I would put in 10w-40 into a car with average/high mileage, only 0w-30/0w-40 for running in oil.
The dealers mostly use 5w-40, so why use thinner oil than this?
Recon i am gonna use Silkolene Pro 10w-40 Fully Synthetic.
This is what i have been told on previous threads and dealers too, so i hope they are right.
 
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Yumann

Full Member
May 17, 2002
1,638
0
Glasgow
Mobil 1 is not as good as its cracked up to be. I ve been running it for the last 10000 miles.
The oil now in my car is thick and black like tickle.

I thinking of using some redline 5-30 or 10-30. Which seem a far superior spec on paper to the mobil 1. eg flash point etc.

But at £84 for 7 litres it is a bit pricey but iam sure well worth it when the hot weather/trackdays come!
 

AndyMills

Full Member
Dec 20, 2004
90
0
Reading
www.virginpowder.co.uk
i wouldn't use the really thin stuff stick with what the manufacturer recomends, i put it in my 16v clio and the oil pressure was really low. I have since heard that you can get mobil1 in different viscosities. what oil do seat recommend?
 

oilman

Forum Sponsor
Ok, firstly Castrol RS 0w-40 is not 503.01 Approved, here is the UK, up to date data sheet.

http://www.opieoils.co.uk/TechSpecs/CastrolRS0w-40.pdf

Secondly, why is Mobil1 the best? If an oil is approved to 503.01, that's it, VAG have tested them and they meet the spec so come on, who's kidding who? Fuchs Titan Supersyn SL 0w-30, Castrol SLX 0w-30 and Motul 8100 0w-40 all meet the specification.

Finally, whats this rubbish about 0w too thin, 0w running in oil?!

Read this carefully and think again before making such statements please ;)

0w-40, 5w-40, 10w-40 and 15w-40 are all the same thickness (14cst) at 100degC.

Centistokes (cst) is the measure of a fluid's resistance to flow (viscosity). It is calculated in terms of the time required for a standard quantity of fluid at a certain temperature to flow through a standard orifice. The higher the value, the more viscous the fluid.

As viscosity varies with temperature, the value is meaningless unless accompanied by the temperature at which it is measured. In the case of oils, viscosity is generally reported in centistokes (cst) and usually measured at 40degC and 100degC.

So, all oils that end in 40 (sae 40) are around 14cst thickness at 100degC.

This applies to all oils that end in the same number, all oils that end in 50 (sae 50) are around 18.5cst at 100degC and all oils that end in 60 (sae 60) are around 24cst at 100degC.

With me so far?

Great!

Now, ALL oils are thicker when cold. Confused? It's true and here is a table to illustrate this.

SAE 40 (straight 40)

Temp degC.........................Viscosity (thickness)


0..........................................2579cst
20..........................................473cst
40..........................................135cst
60..........................................52.2cs t
100........................................ 14cst
120.........................................8.8cst

As you will see, there is penty of viscosity at 0degC, in fact many times more than at 100degC and this is the problem especially in cold weather, can the oil flow quick enough to protect vital engine parts at start up. Not really!

So, given that an sae 40 is 14cst at 100degC which is adequate viscosity to protect the engine, and much thicker when cold, how can a 0w oil be too thin?

Well, it can't is the truth.

The clever part (thanks to synthetics) is that thin base oils can be used so that start up viscosity (on say a 5w-40 at 0degC) is reduced to around 800cst and this obviously gives much better flow than a monograde sae 40 (2579cst as quoted above).

So, how does this happen, well as explained at the beginning, it's all about temperature, yes a thin base oil is still thicker when cold than at 100degC but the clever stuff (due to synthetics again) is that the chemists are able to build these oils out of molecules that do not thin to less than 14cst at 100degC!

What are the parameters for our recommendations?

Well, we always talk about good cold start protection, by this we mean flow so a 5w will flow better than a 10w and so on. This is why we recommend 5w or 10w as the thickest you want to use except in exceptional circumstances. Flow is critical to protect the engine from wear!

We also talk about oil temps, mods and what the car is used for. This is related to the second number xw-(XX) as there may be issues with oil temperatures causing the oil to be too thin and therefore the possibility of metal to metal contact.

This is difficult to explain but, if for example your oil temp does not exceed 120degC at any time then a good "shear stable" sae 40 is perfectly capable of giving protection.

"Shear stability" is important here because if the oil shears it thins and that's not good!

However, if you are seeing temperatures in excess of 120degC due to mods and track use etc then there is a strong argument to using an sae 50 as it will have more viscosity at these excessive temperatures.

There are trade offs here. Thicker oils cause more friction and therefore more heat and they waste power and affect fuel consumption so it's always best to use the thinnest oil (i.e. second number) that you can get away with and still maintain oil pressure.

There is more but this post is too long already so lets keep it to basics.

Cheers
imon
 

Yumann

Full Member
May 17, 2002
1,638
0
Glasgow
Good read oilman!

You guys at opieoils know your stuff :thumbup:

Tell guy thanks for sorting me out with the 2 cans of motul 8100!
 

Pabs

Active Member
May 3, 2004
5,936
4
Basingstoke
oilman, I have Pm'd you a few times but havent received a reply yet.....

What oil do you recommend for an AUQ 2003 Seat Leon 20V 1.8T Cupra that has been remapped to around 230bhp (revo stage 2)?
I dont do track days, mainly motorway driving and some town driving.

My manual only states:
Multigrade synthetic oils, spec VW 500 00.
Brand multigrade oils, spec 505 01 or as per spec API-SH or ACEA A2 or A3.

please let me know!
 

Yumann

Full Member
May 17, 2002
1,638
0
Glasgow
Pabs you should try some motul E-tech ester 8100 0-40 which is 503.01 spec. I just bought some from opie oils at £66 for 10 litres.

It is an ester based oil so should be very durable. And the good thing is it comes in 5l bottle unlike mobil/helix/slx all come in 4.
 
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oilman

Forum Sponsor
Pabs said:
oilman, I have Pm'd you a few times but havent received a reply yet.....

What oil do you recommend for an AUQ 2003 Seat Leon 20V 1.8T Cupra that has been remapped to around 230bhp (revo stage 2)?
I dont do track days, mainly motorway driving and some town driving.

My manual only states:
Multigrade synthetic oils, spec VW 500 00.
Brand multigrade oils, spec 505 01 or as per spec API-SH or ACEA A2 or A3.

please let me know!

If you want the best, then look at the Motul 8100 0w-40, this is an ester/pao synthetic that meets the VW503.01 spec wich is for Cupras post year 2000.

Tech data here http://www.opieoils.co.uk/lubricants.htm

Drop me a mail for a price list.

Cheers

Guy.
 

Mitchy

TTRS
Oct 12, 2004
2,310
0
Interesting post oilman.

Im just about to do a full oil change and im swaying towards 0w 40 Mobil 1. However i am getting temps of 120 C normally and 135-150 when driving very hard.
 

Mitchy

TTRS
Oct 12, 2004
2,310
0
Oil temps mate. I have a chipped LCR.

I have an aftermarket oil temp gauge and plugged the sender into the oil filter housing

Im now beginning to worry about the temps and wonder if i should fit an oil cooler. It may be a dodgy gauge/sender but i doubt it. I'll do a full oil change and fingers crossed it will bring them down a notch.
 

peter1

Guest
Why is it that a lot of people are recommending oils that meet VW 503.01.
This specification is for cars running variable service intervals. SEAT do not offer this with there model range. Now I know that it is an Audi engine etc and they do offer variable intervals. But , I would have thought it better to change an oil at 10K miles maximum(using good synthetic oil) than at 20K (run in with 503.01 oils.)

Variable service intervals have been introduced to keep service costs down, to please fleet companies. Not, to look after engines better.
 

peter1

Guest
What i am trying to say is:
The oil does NOT have to be a VW 503.01 spec if changing it at 10K intervals or less.
 
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