fuel filter light while driving at constant rpm's of 2000 or higher
I have just recently brought this truck back from its shallow grave. It is a 96 f-350 crew cab long bed dually with the 7.3 turbo. It had not run since 2010. I had to put a transmission in it and a steering box some batteries and other misc. parts. So it cranked up within 30 minutes and runs fine. i drove it around all weekend, then finally decide to take her home, to get inspected. While driving around 2300 rpm's or roughly 70 mph the fuel filter light comes on, the truck bogs down and tries to shut off. I shift into neutral take the load off and it idles rough shaking the entire truck back and fourth. It clears up and I carry on down the road. Then does it again and again and again... At slower speeds around 1200-1500 rpm's the truck does fine. The truck used to run on a mixture of things. Burnt transmission fluid mixed with diesel and a little gasoline. Is it possible that gelled up in the lines or the pump or anywhere? Also I did change the fuel filter. Thanks for any advice. Also I am new to the thread and this truck, so I may not know all the technical terms.