I'm back with a lot of the same problems. I posted a thread the other day about -34 degree weather in Maine that reeked havoc on my commute to work. It was -35 last night and the same thing happened. I had it plugged in and it started fine. I let it warm up for about 20-25 minutes. I started of to work and it was fine for about 1/4 mile then all of a sudden it loses power and feels like it is running on one or two cylinders. Here are more specifics. The other day when It happened I put in a bottle of the Diesel 911 that Napa sells. It seemed to do the trick. In fact it ran better than it ever has. I figured my problems were solved. The temp dropped to about -20 the next day and there were no further problems. Today.....Another story!!!! I had a half tank of diesel and it was -35 below! It did the same thing as the other day so I dumped another bottle of Diesel 911 in the tank......Nothing! It took me an hour to get the truck to work. I would have to put it in park and let it idle until it idled smooth then I would get going. It would shift through the first several gears fine then it would no longer shift and the RPMs would get rather high. All of a sudden it would shift to a higher gear with no power "AT ALL"!!! It would then shift all the way through the gears into overdrive with no power to move it hardly at all. I would pull over, let it idle until smooth and then start all over again. We are going to get more cold weather this week and I am in need of some good advice as to what the problem could be. HELP!!!!!