I changed the engine oil. The new oil is: Castrol gtx 15w40 High Mileage oil.
Someone said to me that it´s not wise to use that kind of oil, because the "seal conditioner" in the oil will ruin all the (new) seals. (at this moment my car is not leaking anywhere). Is this true? Do i have to renew the oil immediately?
Volo 240 1993 350.000km
I don't know for sure, but if an oil would ruin new seals then it would (further) ruin old seals too. The material from which the seals are made would be the same either way, and any destructive effect would therefore be the same.
"Tim McNamara" : The material from which the seals are
Ik think the effect will be that because of the "seal conditioner" ,the old seals will swell up and will give a positive effect (maybe stop leaking). New seals(or seals which are in a good condition) will also swell up and will lead to a negative effect (maybe starting leaking). In other words: it will solve a problem and cause a problem.
Maybe. I am skeptical of such claims, perhaps because being a US citizen I am subjected to specious product claims throughout my waking hours- the right of companies to mislead about their products being better protected by our laws than the right of consumers to have accurate information.
The Castrol page for the product focuses on resistance to burn off and little information on the seal conditioners, although I did not have time to read the linked information about the product. I'm going out for a bike ride, it's a beautiful if unseasonably chilly day. Cars can wait. If you're interested, there may be more pertinent information in the links towards the bottom of the page:
no you don't need to switch just one batch of oil; it's not that big of a difference.
Why did you change to 15w40 high milage oil. What improvements are you expecting.
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