Ok, this is my first time posting, I have read numerous boards and can't seem to find a fix.
I have a 2002 F350 7.3, automatic (non-dually), it has around 2003k mi on it. i just recently purchased it in December of 2015. it ran great up until 6 weeks ago. So, what it's doing is, almost every time the trucks shifts, my RPM's fall to 0, even though my foot is still pressing on the fuel pedal. if I let off the pedal and press it again the truck begins to accelerate again. After the RPM's fall to 0 it stays there for about a second and then returns to about 800 RPM's, all the while the truck never dies it just continues to Idol, I let off of the pedal and press it again and it accelerates again.
I have replaced the fuel pedal assembly, the CPS, I've checked the UVC harness on both valve covers, and my truck isn't chipped or tuned. Someone please help, I don't really know what else to do.

P.S. When the Transmission starts to shift the RPM drops to zero suddenly, as if I just quickly pulled my foot of the the fuel pedal.

 

Before wasting money on parts that couldn't cause this you should get the codes read. The places that read codes free CANNOT read all of the codes you need. Go to a good independent shop or a Ford dealer.