I have a 2006 z71. It just started yesterday when going slow turning the steering wheel shakes and it feels like the left front shakes. I notice it when turning left. My wife's 2006 Tahoe did this several years ago and dealer replaced something in the steering but I cant remember what they replaced. I think this was s known problem. Can somebody tell me what guide could be and is it ok to drive like this.

 

Do you hear any noises? Try jacking up the front end, both sides, and spin the wheels while someone turns the steering wheel. Maybe you can feel or tell if something is binding.