So switching to synthetic would be a good thing. Switching back to standard would be what caused the problem?

 

This conversation has been going on (for me at least) since I first switch my car to synthetic in 1996. Truth is, neither dino nor synthetic does anything to the seals unless you run a "high mileage" oil. Sure, it may look like its related, but there is nothing in the oil itself that would cause this.

 

Ok so swithing to a high mileage oil makes seals swell, and then switching back to dino oil will cause them to sshrink again?

 

Most HM oils have seal swellers in them.

 

The funny part was I've hear more people say the opposite; that switching to synthetic makes it leak more because somehow its "slicker", LOL!

As was said above, high mileage oil does have additives to reduce leaking which most people assume, including myself, is a gasket swelling agent. Any other oil doesn't do anything to the seals, I promise.

Obviously switching viscosity is enough to make gaskets leak more or less.

Anyway, I'm not trying to be a smarty pants, just saying that the rumors about leaks and synthetic oil have been going on for a long long time and now manufacturers now post on their websites that switch to and from synthetic has no effect on gaskets. I know I've read that on the Mobil One site with my own two eyes. If I get a free hour, I'll see if I can find it again. You can switch back and forth freely.