I have a 07 LS HHR that I got new with 49,000 miles currently on it. Over the past year or so I have been having a vibration that comes and goes at random times. When I have the vibration and I hit the brakes, the steering wheels shakes like crazy. When there is no vibration while driving, there is no shaking while braking.

Since I started having the problem, I have put new tires on all the way around, new wheels when I changed the tires. I changed the rotors and pads. Had the front end aligned. Changed wheel hubs on both sides.

Still no change. I am thinking about changing the CV axle and front struts. I have read through so many posts about vibration problems but none I have found seem to be quite like mine and most have no resolution.

 

How about your tie rod end links or tie rod bushings ... Just throwing that out there

 

Welcome to the site!!
Have a look at your lower control arm rear bushings, I have a 07 LS also, the LCA bushings were shot at 63,000 miles!

 

Have you looked at the rear hubs?
There is a link in my Sig that May help.

 

I finally had a chance to put my car up on jack stands yesterday and was checking for worn bushings or any loose parts. I put my hand on the sway bar and tried to wiggle it to check the end links and the sway bar flexes. Should the sway bar bend a little or not at all?

 

If the bushings are good then no it should not move by hand, I would suggest new bushings and end links if they are that loose.
Those rear LCA bushings may also be shot at that age and milage

 

I was saying that the sway bar, the metal part, would bend. I thought it should be rigid and not flex. The bushings seemed good all the way around but I will probably replace them anyways.

 

I've never seen the swaybar bend, it is a 1 inch bar of tempered steel. It may appear to flex up and down on one side because the bushings are shot, then the same optical illusion from the other side