Jeep: Lifted jeep steering wheel shakes till about 20MPH, rear drive shaft, drive shaft

Question
I have a 98 wrangler 4.0 3"body lift 4"suspension and 33x12.50x15 and after i installed the lift when i start driving there is a vibration in my steering wheel it works itself out kinda after 20 MPH but as i slow down in that range it will do it again.. is this because of the alignment???  

Answer
I would have the alignment checked. The actual alignment does not cause shakes, you usually have parts worn out that cause shakes.  One of the most common problems is the track bar is either worn out, or loose.  Your problem also sounds like it could be a tire shake. If its a really fast vibration it could be you rear drive shaft if its factory, could have too steep of a pinion angle.  Hope you get it fixed!