Mine does the same thing. Don't know if its normal or not as this is the first diesel I've had. I just swapped my e4od out for a 4r100, but never drove the truck with the e4od in it as it was blown when I got it. But I've got a 4r100 behind my other trucks v10, and it definitely doesn't shift like that.... or maybe its just not as noticeable because it has 3:55 gears and not as much torque as my diesel with the 4:10's?? Either way, I'm still on a mission to find out if it really is normal or not, or if the TC is locking/unlocking when it is not supposed to be.