I have an 02' PT cruiser
New problem/ after driving about 200 miles, any road irregularity or bump
will cause the front end to shimmy dramatically. this is at speeds of 60-70
mph. If i let off the accelerator it stops immediately. If i accelerate it
gets worse unless I accelerate quickly, then it finally goes away. Then as I
am coming to a complete stop from about 5 mph the steering wheel shakes
violently.

I have replaced calibers and rotors and the tires have been checked for
separation. Again this only happens after highway driving of about 3 hours.
If the car cools down for 5-10 minutes the problem can not be duplicated.

Has anyone else experienced this?