I was looking for something on octane and tripped over
http://www.chevron.com/products/prodserv/fuels/bulletin/diesel/ and of course the timeline for low sulfer diesel http://www.chevron.com/products/prodserv/fuels/diesel/ulsd.shtml John 1983 300TDt 362k Kilometers (mobil 1 Delvac) 1990 300TDt 164k Kilometers (mobil 1 Delvac) 1993 500SEL 172k Kilometers (mobil 1 0w40)
