I was driving my wife's Expedition today and noticed something, not sure if it is anything or not....at around 60-65 (well that is what I was driving it at). I notice that every once in a while the tack would show an increase of 200-300 rpms and the back to normal in a couple of seconds(in overdrive) seems like I could feel a shift just not sure....What the heck is it? Anything to worry about? no other tranny issues. Thanks

 

What you describe is nothing more than tour torque converter lock out. If you put the truck under a load it may not down ssift to a lower gear but will unlock the torque converter. The torque conver locks into dieect drive ( no slipping ) to get better fuel mileage.