OK...I searched pretty extensively and came out of it more confused than when I started...'90 300E, 148k miles, very well maintained (with Dino) since birth, no leaks, excellent compression - and as a friend described it - a "new" 12 year old car. As many members here do, I pamper my car and don't even want to consider anything that could possibly shorten it's lifespan. I am considering going to a synthetic oil. I live on the NC coast and temps only occasionally dip into the teens, but overall mild temps. Experience preferred, opinions accepted. Should I change to synthetic? If so, what brand? What weight? Should I stay with Dino? I need some experienced advice and look forward to input from the pros...Thanks in advance, Bill