Once you use synthetic oil, can you go back to normal oil?

A mechanic told me today that once you switch to synthetic that you cannot go back to petroleum based oil. I think he's lying.


Another mechanic in a colder climate told me that he uses synthetic in the winter and normal during the rest of the year.Once you use synthetic oil, can you go back to normal oil?
You sure can switch back and forth or even mix the two-- after all a synthetic blend poses no problems. I choose not to mix them because I don't want to dilute the performance of my high quality synthetic oil (Amsoil). Here are some other myths about synthetics: http://www.amsoil.com/redirect.cgi?zo=14鈥?/a>Once you use synthetic oil, can you go back to normal oil?
it won't hurt it one bit that first mechanic is a thief and a liar(thief because he is trying to make someone buy the more expensive oil by lying about it)
should be no difference. sounds like he wants to sell you the more expensive of the two.
I don't see any problems occurring from switching between Synthetic and conventional oils.
your not supposed too - but i suppose its your car, you can do whatever you want ya?
There was some big mystique around the regular vs. Synthetics thing for a while, that you should not just switch back and forth without doing some weird flush or something. My mechanic says that is nonsense, you can switch back and forth whenever. He likes synthetic blends for cold climates. They cost nearly the same as regular and some people feel they protect the engine a little more in cold weather.
switch anytime you want, it won't hurt a thing.
you can go back-n-forth any time. you can mix both. If it is a lube then it does its job.
I've also heard that it is not recommended. Maybe the other guy gets away with it because of a different climate or maybe his car is an older one, but why take the chance. Cars are expen$ive to repair. Different mechanics go to different schools and learn different techniques. Ask someone who graduated from Wyo Tech ... that's the best school!!!!!!!