semi vs. full synthetic

[Bertje]

Registered
Member # 9956

posted 04-19-2005 05:06 PM
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Hi all,

How bad is it for the engine to use one year fullsynthetic oil and the next year semi-synthetic oil? Last week the garage has put semi-synthetic oil in the enigne, while I've been using full-synthetic oil for years.

Is it better to keep using the semi-synthetic from now on, or is it better to throw in full-synthetic oil next oilchange? Or should I change oil rightaway?
Thanks in advance.

p.s. It's a '91 Chevy Caprice 5.0

 

[Triple_Se7en]

How bad is it for the engine to use one year fullsynthetic oil and the next year semi-synthetic oil?

Next year, you may want to use the blend again. Some vehicles prefer one over the other.... time will tell with your Caprice. As long as your engine is not runing hot all the time or the weather gets below 0 degrees if you're using a little thicker oil, then all you need to do is change the oil a little sooner... (1-2K shorter of a typical 8K synthetic OCI )

 

[Bertje]

Thanks, how can you tell if a car is more suitable for semi or for full-synthetic oil?

And do I understand you correctly that I should use semi again from now on, and not change to full-synthetic back?

 

[Ugly3]

There is no problem switching from full to semi synthetic at any time. If you find better economy, less consumption, or whatever, use the oil that best meets your needs.