Not knowing what oil is already in the engine, what type am I safe to put in? Do I need a particular type or am i relatively safe putting any in?

 

What model?
Chances are its a 10w40 semi synth anyway

Tony

 

Use the best you can afford. It should be at least 10W40 and I use 10W60 fully synthetic Millers. There are always mega debates about this. If you are topping up I cannot help because you should not really mix your oils. If it is an oil change then go for the highest spec you can afford. I expect that others will disagree and you may get several hundred confusing replies. Subaru recommend 10W40 synthetic. If you go on the Millers website (Millers is a very good make of oil - but you do partly pay for the name)they recommend 10W60 if you use 10W40 - especially if you do fast driving or track days. The Millers is triple esther oil. Your Turbo runs at up to 900 degrees so really gives your oil a hard time. I have checked all this out with about 12 racing teams now and they all say roughly the same thing. I can also recommend an engine flush with Forte and maybe an injector cleaner by the same folks.

I hope that helps.

 

Confuses the hell outa me too! 10w40 seems to be the recommended oil (for lowly WRX) but then I'm not sure what type / make to put in Recently topped up with Castrol GTX ...

TX.

 

Dont engine flush subaru's and a 60 rated oil is too thick (its twice the thickness of a 40 rated oil), but in 90+% of cases the 10w40 semi synthetic is more than sufficient (including the fact its running in a turbocharged engine otherwise the manufacturer would not recommend it).

Tony

 

RCM put Silkolene Pro R 15w50 in my modified 03 WRX. They always have done and when i had it serviced before them, the other garage also used the same.
Mind you, it is not so critical for me doing 40mph on Nottingham's ring road all the time! LOL.

 

Ty guys

 

 

Why not? It was done by a guy who races them and builds engines for racing cars - he recommended it! Interested to hear your reasons for that, because all of the garages I work with who do the top end racing and motorsport stuff recommended that.

I had several long debates about the oil rating and the result was using the 60 rating to keep the oil stronger at the higher speeds and temperatures.

But I do agree that the manufacturers do a lot of testing of their products and one should follow their instructions. I have been in the engineering business now for 34 years and it is always interesting reading and participating in these debates. I genuinely like to know reasons for things - but most cannot actually give reaons. Rather than bog this thread down Tony could you please PM me with the reasons why you gave me that gen as I would like to see what your reasoning is as well.

Not disputing you though!!

 

Terry, the flush can sit in places in the flat 4 engine that, well lets say cause issues with oil supply (well not issues, just not enough of it and that can lead to bearing failures ) so its not recommended, but if your worried then more regular oil changes can help there

On the other issue of a 60 weight oil, I always like to see it as this (and sometimes thicker is not always better ) you can either run orange juice around your engine or you can run thick milkshake, that 60 is a thick milkshake as your engine doesnt get hot enough for it to do its job at the top supposedly BMW M3's run a 10w60 because they need it (read that they hit over 150 deg in the sump), otherwise your just causing engine drag due to the oil and as its still thick, not as much lubrication over surfaces and it will put more strain on your oil pump (theoretically).

Tony

 

Cheers mate,

I will diplomatically ask the question next week. He has been racing and servicing Scoobs for years, and the reasons for the 60 rating is that although the sump only gets to about 120-130 in mine the turbo gets much hotter and it is that I was trying to protect, but I do understand exactly what you are saying. We sat down and did the maths for quite some time before I finally decided to try the 60 this time, but she will get a change very regularly anyway as I work in the business and it is cheap enough for me to get the stuff - £25 for the Millers last time. I will monitor it very closely, lol.

Have a great new year everyone!