im not big on repairing autos... but ive been around the block and my jeep has me puzzled. i have a 06 jeep wrangler x , and all is well.... until i hit 50 mph, then the vibration starts from the front driver side.... when i hit around 57 mph, it smoothes out and the vibration is gone... i have changed the tires, rotors, and brakes... i will get a front end alignment soon, but im not sure thats my only problem. i have yet to take the jeep off road.... and ideas????  

I did not see bearings on the list of things done and I would get a good alignment check on it before hitting panic button here.  

Was it a vibration or "oh crap, I'm going to crash and take out a bus of orphans"?  The later is DW however, the alignment "should" take care of it but you should also check out your track bar and make sure it's torqued down to proper specs, if that's ok, then check the ball joints.  

and get the balance checked on your tires again, it doesn't take much to throw the balance off