I saw a sticker on the pump today indicating law sulpher content of the disel fuel according to new standards. How this fuel will affect 2001 Duromax? Is it better for injectors or worse?

Check out the "Fluid Discussion" section. LOADS of info there.

http://www.dieselplace.com/forum/forumdisplay.php?f=14

http://www.masstransitmag.com/publication/article.jsp?pubId=1&id=340