Originally Posted by tnfastbusa
i also noticed that the truck sounds like it shuts off at 40mph when you slow down is that normal and it is a auto
You mean that it just drop to idle, or the engine actually quits running? A Powerstroke is about 95% electronic and 5% mechanical. When you are crusing down the road and let off, there is a sensor on the go pedal called the IVS (idle validation switch) that will return the truck to idle. There is also a TPS on the go pedal that sends a signal to the PCM telling it how hard you're pushing the skinny pedal.