Procedure in Going Full Synthetic

I currently have dyno oil and want to go full synthetic, Mobil One, do I have to flush the system, if so, how? Also, I was told if you go synthetic
you can't go back to dyno oil because your seals will go bad, is this true?

Never heard of the seals going bad switching from synthetic back to dino oil. Typically, synthetic will find leaks that do not occur with dino oil.

I did not flush when I went to synthetic. Just do a normal oil change and fill with Mobil 1 and you will be fine.

//2000CAYukon

FYI; synthetic oils will leak where regular motor oil wont due to thinner viscosity. :2cents: ..........Mike

Never heard of the seals going bad switching from synthetic back to dino oil. Typically, synthetic will find leaks that do not occur with dino oil.

I did not flush when I went to synthetic. Just do a normal oil change and fill with Mobil 1 and you will be fine.

//2000CAYukon

That's the way I did it and everyone else I know. I heard the same complaints about leaks beginning when changing. I changed my Harley and the wifes car and no leaks.

FYI; synthetic oils will leak where regular motor oil wont due to thinner viscosity. :2cents: ..........Mike


NEVER! 5w-30, or what ever oil your using, is a rating. It will perform exactly the same as old school oil that is rated the same. (If they both carry SAE logo).