[T240]

Roy, I'm sorry, but it is scientifically impossible to make a w20 or w30 oil perform as per a w40 at high ambient temperatures, no matter how much high tech you throw at the problem.
As I wrote earlier, and it is a well recorded fact, that MB went through a phase of recommending w30 oils for all temperature use, and landed themselves with massive warranty claims as a result.

You obviously haven't even looked properly at the Castrol Uk site - where EVERY regular engine oil is referred to as GTX somethimg or other; i.e GTX, GTX Magnatec, etc. the site is NOT up to date, and that is witnessed, not least, by the fact that the 'fact sheets' are out of date and don't even recognize that many of the oils listed are out of production, as stated previously. Plus, as with the US site, many of the options just aren't functioning. i.e selecting an operating temperature.

As for Volvo using fully synth oils from the factory, I have never talked about NEW engines in relation to this subject, so what relevance you think it has is purely in your head, as does bringing air travel into this conversation!!

"Only a fully synthetic can properly protect the modern turbo charger" - Quite frankly, that is palpable nonsense!


If you don't care to research this subject properly, then, quite frankly, Roy, it is your problem, but really you're way out of your depth here.

Cheers,

T