Based on what I have found out about motor oils both prior to coming to this web site and especially since I have come to this web site, I have been able to narrow down somewhat the list of motor oils that I would be willing to use in a car or truck engine. For conventional motor oils I like Chevron Supreme, Pennzoil, Castrol, and the Schaeffer's conventional. The Chevron Supreme made my car run very smooth. I have not actually tried the Schaeffer's conventional, but based on my experience with the Schaeffer's blend I am confident it would be outstanding. For blends it is hard to beat the Schaeffer's blend. I have not tried but am interested in the Mobil Drive Clean Plus blend. For synthetic oils I like Mobil 1 and the German Castrol. I have tried Amsoil but it was the XL7500 or whatever they call it-apparently not a PAO or ester synthetic. I have never tried Redline and I can't say anything about it. Auto-RX is one of a small list of oil supplements that I am willing to use. Neutra is great in small amounts in the gas to keep the fuel injectors clean.