Is Amsoil really the best motor oil available for most cars and trucks? Recently people have been posting the results of various tests that have been done. Of course, much of this testing was done by Amsoil and you can expect that they will put their motor oils in the best possible light that they can. And I personally don't agree with some of the testing such as the four-ball testing. I don't think you can really compare motor oils with that sort of test. But unless the Amsoil people are flat out not telling the truth the Amsoil DOES look good in all kinds of different testing. In comparison, even Mobil 1 seems to look poor in some of the testing. But some motor oils, such as Redline and Royal Purple, never seem to be tested by Amsoil as far as I have been able to determine. Perhaps these motor oils would perform as well or better than the Amsoil. Of course, you have to take advertising with a grain of salt. But you have to give Amsoil credit for naming names and publishing actual test results that compare brands of motor oil. How many other people do this sort of stuff? And when you names names you better be correct because Amsoil could be sued by another company if they flat out lied in their advertising. If we can assume that much of the testing is totally correct then Amsoil would have to be one of the top motor oils-period. Maybe THE top motor oil.