First I wanted to say this site is a great resource. Here is my question. I have recently purchased a brand new 2003 Mazdaspeed Protégé. Until I found your site I had planned on the following. To change the oil after the 600 mile break in period and use Mobil 1 0w-40 oil with a Mobil 1 oil filter. I liked the idea of having a 0w oil for cold start purposes and the higher 40 rating because I live in South Texas were it gets very hot in the summer. This is my first turbocharged car and I wanted to use a synthetic oil because I know that a car with a turbo is tough on oil. After searching on the site I have found mixed reviews for the Mobil 1 0w-40. I would be using a 5000 mile oil and filter change interval as this car is my daily driver. What do you guys think? I am open to both oil and oil filter suggestions. By the way the owners manual recommends 5w-30 or 10w-30. Thanks.