synthotic oil

I run Amsoil Zrod oil with a wix fliter in my old cars and have nothing bad at all to say about it. I also run Amsoil 15w40 diesel oil in my cummins truck with there filter. I guess everyone has there own idea of what oil to run and that seems to be mine. You have to watch as alot of synthetic oils are not 100% synthetic and are just a blend.
Matt