There has been so much debate over that. Realy don't know what to believe. Just my own personal thing to stay with the dino oil though. Not that I think syn is bad just because I am old and set in my ways.

i think ill go with the thickest syn that i can find, not gonna hurt anything if its on its way out anyway

dont waste your money on synthetic for a 200k motor, just put 20-50 in there

I've always used synthetics. On the motors ive taken apart everything looked peachy!