I bought this truck used in 03 and was not that familiar with diesels. I knew you had to plug them in when it got cold. That is an understatement. If you dont your gonna have a heck of a time starting. I bought a quart of Synthetic Oil Stabilizer and put in the oil. And now I dont have to plug it in (with a help from a anti fuel gel) but it cranks over easily in the cold and purs beautifully. This is a great product. I suggest it to everybody no matter what they drive.