I had problems with the Superchip on my 2000PSD F-250. erratic shifting and felt like it was slipping on a trip to Ensenada, Mex. sand dunes. On the trip back I decided to trade it in for 2001 F-250 V-10, Before taking the PSD to trade it in, I took the chip out, the problems cleared up completely. I went through with the deal for the V-10 anyway and like it a lot better. No more hunting around for diesel, and having to turn the motor off at drive-thru windows cause of the noise.