It could be the pre load on one bar has changed. My suggestion is to have some one there to help you do this. If you can get underneath without jacking it up this will be more accurate. If you can't then you need to duplicate the way it sets as close as possible. Take the top left bolt out of the bracket on the housing or on the frame. adjust the length so the bolt slides in and out with you in the drivers seat. Have at least a half tank of gas. The better you duplicate the driving conditions the better this will work. If you have to jack it up make sure you have the same amount of rake you do on the ground. My 2 cents.
Ken