I like this oil for turbos too. It's the most shear stable of the Amsoil 30 weight formulations, with very little polymeric thickener (VI modifier). I see lots of people using 0w-40 in turbos - but that's exactly the wrong thing to do. Every 0w-40 uses a lot of polymer and will shear down like crazy in a turbo. If you feel you need a 40 weight oil, a 5w-40 or 10w-40 will maintain its viscosity much better....