Okay, I'm not really that awesomely smart with this truck stuff so bare with me please. For a while I was hearing a loud clunking noise when I was turning the wheel, and then I noticed recently that the steering felt like it had a lot more play than usual so I took it to a buddy of mine and he found that where my idler arm was bolted to my frame was completely busted out in two spots. He welded in a patch for the frame, but said that it wont hold for long unless we find out why it did it. Now that the holes are fixed I can feel the strain on the steering, and can tell when the power steering kicks in and really has to force the wheels to turn. I found another guy in an online forum that had a '97 k1500 with the same 6" pro comp lift on it, and his did the same thing. My buddy thinks that these two parts on each side are froze up which is causing the strain on the steering. But the newer version of the pro comp lifts don't appear to come with these parts anymore. We're not even sure what these are called, what they really do, if they are needed, how to get them if so, etc. If anyone has any info pleaseeee let me know.
Ok there is your answer in your question. You have a 6" pro comp kit in it and i'd bet withut seing the suspension that it has all the STOCK components in it other than the lift kit. It is straining your suspension and the ONLY FIX for this is to have the rest of the suspension pieces installed that it requires OR to put it back to a stock system meaning take the lift kit out. Otherwise you will run into the very same problem. Those tires that are on there assuming that they are oversize put to much strain on the stock suspension causing your problem. If you go to like powerblock tv they have videos that expalin this on the Trucks and XTRREME4x4 segments as well as turck U on speed channel. If you have what is called the "death wobble" then you should do one or the other the death wobble is when you let off gas and your front end goes kind of crazy for a while. All those tv programs explain it. You can watch it right on your computer just look for it in the videos.