But I don't know or understand what regan is that I keep on reading about. I am think about making the jump to PSD and want to know what this is, how it happens and how to prevent it.

 

On the new diesels built after 07 they had to have a Particulate Filter and they put extra fuel into it and it burns the soot that it collects. You can buy kits to delete them but they are not cheap. Here is there website.

http://www.spartandieseltech.com/