So I'm looking at buying a tow rig. I test drove a 1985 K20 suburban that is in surprizingly good shape. On the exhaust right as it exits the head, it has tubes that come up from each cylinder to a box on each side of the manifold - any idea what it is - smog stuff? Then I drove a 1984 K30 Crewcab 4x4. I was following the guy to his shop and twice he experienced what I guess is death wobble. I was driving behind him and could see the bottom of the front wheels moving 6-8" back and forth on a horizontal axis instead of the vertical axis. So, is this DW and is it easier to fix on a stock truck?