Matt_Turbo_2000

Hi cant find RS anywhere will Castrol GTX Magnetec 10-40w do the job? Also MY00 Turbo take 4.5 litres of oil doesnt it?

BigGuy

I do not advise the use of Castol Maganatec. I recomment Castrol RS 10w-60, Motul 15w-50 or even Mobil 1 15w-50. With filter change it takes exactly 4.5 litres.

julian N/W wrx my93

so why does the book (and subaru sometimes) recomend 5w30 fully synth?

i keep asking and no one seems to know!

Matt_Turbo_2000

will use Mobil 1 15-50 then coz halfords sell that have seen Millers CFS 10W60 that would do wouldnt it as its a fully synthetic oil?

greasemonkey

Mobil 1 15w/50 will be fine. Don't simply bung four and a half litres of oil in, BTW, as you could end up overfilling it. It's better to start with however much the filter takes when you pre-fill it (likely to be around half a litre), then add another 3.5 litres to the sump before using the dipstick.

The optimal change technique (along with a load of other good stuff) is detailed here.

speedking

Castrol website.

Matt_Turbo_2000

Asked subaru CVC Cardiff and they said that I should use Valvoline SynPower 5-40w fully synthetic and that what I have used seems to be ok they said I should use it because it offers better protection from cold.

Fangoria

iTrader: (1)

5/40 is too thin for a Subaru Turbo - well at least one thats been modified in any way

As peeps have said before stick well clear of Magnetec - sludge - bordering on useless

Others have given the correct stuff - best is claimed to be Motul 15/50 which you can get from Demon Tweaks - 01978664466

Halfords had run out of Mobil 15/50 when I called yesterday into all the ones in Bristol so I just ordered 20 litres of Motul from Demon Tweaks - its not cheap though at about £10 a litre (Inc Vat) - I think there was a group buy on the stuff lately but group buys are getting to be too much hassle lately - especially if NF booster was anything to go by!!!

Fangoria

iTrader: (1)

btw - my sti5 takes 4.7-4.8 litres..... not 4.5 litres!!

Jiggerypokery

My local subaru garage use Castrol GTX Magnatec 10W40, and say the oil doesn't need changing more regularly than 10k miles.

The magnatec has been in for about 1k, is it ok for another 2-3k before I change it myself, or should I get it out of there?

greasemonkey

Hmmm. Is that the only Subaru dealer in your area? If not, it might be worth driving a little further.

It'll be alright for another couple of thousand miles, provided you don't do any trackdays. After that, change it out for something better. One of the oft-recommended full synths provided your car has more than 10,000 miles on it, or something like Shell Helix Plus 10w/40 if it's still newish.

Matt_Turbo_2000

Originally Posted by Fangoria
5/40 is too thin for a Subaru Turbo - well at least one thats been modified in any way


whoops that must mean all the main dealer serviced subarus in south wales must be running round on the wrong oil then!

Fangoria

iTrader: (1)

Well thats why I put the extra caveat in

Cripes I wouldnt even have used 5/40 on my previous Ford cars - various Turbo's

Given the service intervals seem to be a little longer I'm stunned that Subaru dealers use 5/40 - oh well at least I'm sure Subaru UK have taken into account the possible additional warranty claims from choosing this route

For all imported vehicles and ones running in excess of 250bhp I wouldnt dream of putting in anything less than 10/40 or preferably 15/50

Like others have stated if you do a track day 5/40 oil will break down very, very quickly and really at heat its too thin - you takes your chances - I'm not - then again I have an sti5 so I've never had it serviced by a Subaru dealer........ i.e. I get it properly serviced!!!

I'm just in the process of buying a new wrx - it has 3 yrs free servicing - I think I'll be giving it my own interim service!!

BigGuy

This was faxed to me a couple of years ago. As I can't seem to understand how to scan it and attach here I typed it word for word:

SUBARU Technicnical Service Bulletin No 1-1B-015

Please Circulate To : Service Manager/Workshop Personnel

From: John Baker, Subaru (UK) TechnicalService Department

Subject: Mobil1: 0W-40 Engine Oil

Applicable Model/s: All Subaru Turbo Models

Subaru UK technical department have recently been receiving a large number of queries from both the Subaru Dealer Network and Subaru Turbo Owners, relating to the use of Mobil 1 0W-40 engine oil and the companies official policy regarding it’s use in our 2.0 Turbo engine.

The only engine oil specifications we would recommend for use in the 2.0 turbo engine are oil grade API classification SG, SJ, SH, SAE viscosity 10w-30, 10w-40. Using a SAE 5w-30w or lower viscosity for the turbo models is not recommended, as stated on page 10-14, 10-15 of the Impreza Owners handbook A1790GE page 10-14, 10-15.

Matt_Turbo_2000

As I understood it 5-50 meant 5 is the low temp flow rate and the 50 is the high temp flow rate so 5-50 is better from cold and offers the same high temp flow characteristics as say a 15-50 oil! So why do you all go on about 5-50 is too thin that is what you need when you first start your engine not thick sludge that takes ages to get moving see below.


http://www.geocities.com/Yosemite/Go...motor_oils.htm

Viscosity:
One of the main areas of concern of any car/truck owner is the viscosity of the oil. The term "weight" has been applied to viscosity for a number of years, but it has nothing to do with how much the oil weighs. On any oil container, the viscosity is clearly marked, with numbers like SAE 0W-30 5W-30, 10W-40, 20W-50, etc.

What do the numbers mean?

Viscosity is defined as the physical property of any fluid to resist flow when pressure is applied. The Society of Automotive Engineers (SAE) uses a numbering system to represent an oil's viscosity at a specific temperature. The higher the number, the more resistant it is to flow. The lower the number, the easier it flows. This allows you to make an "apples to apples" comparison of various oils.

Engine oils must operate in very difficult environments, plus perform a number of important tasks:

It must flow easily at temperature well below zero.
It must supply lubrication at very high temperatures (in excess of 250°F).
Lower viscosity oils flow well at very low temperatures, they are the choice for severe winter operation. Obviously, the ability to flow readily is critical to start your vehicle's engine in brutal cold, and calls for a lower viscosity, such as 0W or 5W viscosity grade.

For protection against high engine operating temperatures, oil must be able to function and provide the needed lubrication. When the vehicle is operating in summer heat, with temperatures above 80 to 90 degrees day after day, the need is for a high viscosity oil.

But do you want to change grades of oil every time the weather gets warmer or colder? Probably not. This is why there are engine oils with two viscosities on the market, known as "multi-viscosity" oils. These oils carry the low temperature flow, and high temperature lubrication properties of the two oils, such as a 0W-30. The "W" refers to winter, with a special additive package to give better cold weather starting performance. As an example, under high heat, OW-30 will have the same flow characteristics as a 10W-30 because their "high numbers" are the same.

Synthetic Oils will handle both the high heat of the Desert Southwest or the cold cranking demanded in Alaska! Many of them have pour points are as low as 76 degrees BELOW Zero!

The issue of engine oil volatility is an important one to every car or truck owner, yet few know about it. Volatility is related to viscosity. Volatility is defined as the characteristic of liquids to become a vapor when heat is applied. A liquid is said to have "high" volatility if it tends to evaporate when heat is applied, and "low" volatility if it tends to remain a liquid when the same amount of heat is applied.

To meet the federal government's fuel mileage standards, auto makers tell owners to use lower viscosity oils. Unfortunately, low viscosity oils tend to evaporate more easily than high viscosity oils. The problem: Using a low viscosity oil generally leads to what appears to be an oil consumption problem, when actually the problem is evaporation - the most fuel efficient oils evaporate most readily.

speedking

But the original question asked whether Castrol GTX Magnetec 10-40w (actually 10W/40 ) would do the job of Castrol RS presumably 10w-60. I think we are all agreed that it will not.

The new question is whether 40 or 60 viscosity is the best?

deano555

Try giving Castrol a ring, they will tell you to use magnatec 10-40 semi synthetic, if your car is still under manufacturers warranty and the TWS motorsport if its out of warranty. I did a interim service on mine at 5000 miles (my03) with magnatec and it is fine. But I will use fully synthetic after 10,000 miles.

dba

The new question is whether 40 or 60 viscosity is the best?

possibly nothing for normal road driving,but a big difference on a track at high temps,the polymers in the 60 will hold together wheras the 40 may break down