Okay here we go. I have a 1987 190e 2.3-16V that has been using castrol gtx oil. I was thinking of switching to Mobil 1 synthetic oil. Is that worthwhile or should I just stick with the Castrol oil? Also, is there any harm that could come to the engine from switching to synthetic oil? Appreciate all the help!

Your car has operated on "dyno" oil for 17 years. What would be the point of switching to synthetic at this stage?

There is a member here who goes by the name of Jackd.

He's apparently been involved in oil testing/research for many years.

Look for his posts and see what he thinks about the whole synthetic issue.

Thats what I figured. I kind of thought there wouldnt be any advantage to switching. Thanks!