When I bought my wife a new Prius, I decided to keep her old one (2004) as a small run-around and parts getter for my Jeep (my obsession and money-pit). I have noticed that the Prius seems to shudder and clunk in and out of electric / gasoline mode. My wife says it has always been that way. I do not recall noticing it before and I am not sure that she pays as close attention to things automotive as I do. So...is this normal in the older hybrids? Should the shift between gas / electric modes be smoother or is the shudder and clunk normal? The power-train (including the hybrid system) is covered under Fairfax Toyota's "Auto For Life" program, but I do not want to waste the trip and the diagnosis fee if this is normal.