01-23-2009, 02:46 PM
mikebw wrote:
I have read that switching to synthetic on an older engine may lead to leaks that were not apparent before. The synthetic oil may find it's way through some worn seals and gaskets that the dino oil may not have. Of course I don't know that to be true, first hand.
Seconded. Dino oil tends to gunk up the seals more, possibly hiding potential leaks. Synthetic oil usually have more detergents in it that will ungunk your engine to some extent and may reveal leaks that were plugged by gunk. It's not a certainty that this will happen, just a possibility.
I'm all for using synthetic initially in an engine, and it you do so, there is no reason to not keep using it. But I am wary of switching to it in a much older and well used engine.
Why mess with it if it's running well?