Truck wont accelerate even when I've got it to the floor
 

I have a 2003 3500 diesel. This morning it was about 5 degrees out. I started it as usual. I got on the road and accelarated as usual through the first 2 gears. When I got to 3rd gear I could't get it to accelerate once I hit about 1200 rmps. I've put an anti-gel solution in the gas line but that isn't helping. Bad fuel filter? or bad fuel pump? any other suggestions?

i'd blame gelled fuel if you havent been having any problems prior to this and the temperature you indicated would cause that. if you know for a fact that the fuel is still liquid it is probably the fuel pump

I had a similar issue a couple weeks ago. It would not rev above 2500 rpms and lots of white smoke but a new fuel filter and air filter did the trick. It runs great now.

all your boost hoses on and tight?