2001 Blazer front end squeaking/vibration when turning slow

I have looked all over and can't seem to find an answer so I hope someone can help me.

I have a 2001 Chevy (trailblazer edition) with 160k miles. In the past 6 months I have tried to get rid of this horrible sound. When driving, no matter how fast or slow, my blazer makes this sound like somebody bouncing on an old mattress. The squeak is horrible! To add to this when I am slowing down, say to turn into a parking spot, I get a vibration from the front end up to the steering wheel. Vibration only when turning.

Here is what I have done:

Replaced shocks, both front wheel bearings, pitman arm, steering box, inner and out tie rod ends, idler arms, center link, new tires, alignment of course after all this. Now most of these items needed to be replaced and they where not all done at the same time but fairly close togther.

An oddity is that when someone who weighs 200lbs or more sits in my front passenger seat while I am driving all these noises and vibrations go away.

What is going on here? What am I missing? :screwy:

Could be a broken sway bar end link, dry sway bar mounts, dry control arm bushings, dry torsion bar sockets or mounts, could even be the rear leaf springs rubbing together. Try a healthy shot of lithium spray grease on those areas, (one at a time so you know which one it is) and see if it quiets down.

Great suggestions! The sway bars were replaced about a year ago, so hopefully not that. I will give this a try this weekend and update everyone.