Whether you currently own a diesel or not, you likely know that it takes some effort to keep it running right in the winter months in cold areas... in Alaska - so I've heard - most guys drive around with a junction box under the hood with all their "heaters" plugged in, so they only have to plug in one cord to the outlet. Block heaters, oil heaters, fuel heaters, tranny heaters... all help a truck run in damn cold weather... Then you have Winter Blend Diesel fuel, the stuff that is supposed to help your diesel run better in winter because of it's lower cloud point... but you lose power with winterized diesel, and so everyone and their mother puts additives in their tank to get that power back (and to boost it further in Summer in some cases.) There are so many different additives on the market right now, and no one really knows which one is best for your engine. It may be a personaly preference on which type of addititve you decide on, but you owe it to your truck to do as much research as possible on what you decide to put in the tank. I don't mean to cross post, and it really isn't my idea of a cool thing to do, but thousands of people a day come through the garage, and since I posted this last night in the diesel forum, I've had 20 looks and no replies. So with that, please check out http://coloradok5.com/forums/showthread.php?t=192204 I may be offering this additive soon, depending on my own testing with my truck. This additive is the only one on the market that didn't have to change their formula to work with ULSD, and meets all standards for a diesel fuel additive. It is an American company that has been around since 1918, so you know they aren't going anywhere soon. Check it out... if you like it, send me an e-mail, and when I get my order, I'll ship you a bottle to try out too.