The 2-step?

Yeah , when you get your foot in it good, she feels like she`s just barely touching the ground. If you hit any significant bumps the front end kinda` does a little jig or "2 -step". It also happens if you`re cruising fast and you hit a good pothole. The engine is a mildly built 440-6 with a 4spd. The car`s always done it, even with the 383 in it and I`ve had other Mopars that did it too. ?