2009 Rogue bouncing

[abrock0084]

Recently had a tire with a slow leak, so I added some tire slime and air. Since then the car bounces really bad. It could be unrelated, but it was fine until that was done. This worse than a vibration or shimmy. If you are in it you literally bounce. This occurs only during acceleration between 60 and 80 mph. If you run 90+ or under 60 it is fine. I had the tires balanced and rotated and there has been no change. If you are running 80 and let off of the gas it stops, but as soon as you touch the pedal it starts again. It also feels like waves (only way I know to describe it). It almost feels like it's revving, but the RPMs are not fluctuating, so it's not actually revving. Any idea what this could be? Brakes, rotors, and a front passenger wheelbearing were changed a few months ago. Tires appear to be fine and the one is not leaking anymore. I wasn't very sure about it being a tire issue since it only does it during acceleration. Thanks for any suggestions or ideas you all can offer!