Pontiac Repair: shake in my car, 2007 pontiac g6, pontiac g6

Question
QUESTION: "my 2007 Pontiac G6 has a shake in the front when it first starts to go but then stops after it hits about 15mph. the rotors and breaks have been changed and the tires have been rotated aligned and balanced... any idea what the problem could be?

ANSWER: Hi there!

I would have the tires road force balanced. you could have a couple of bad tires on this and when you roated the tires another one wound up on the front.. does this have any kid of noise or shimmy on sharp turns? that could indicate an issue with a drive axle which may me a cause of the shimmy as well. If this has continental tires on it I would really suspect a bad tire first and foremost.


---------- FOLLOW-UP ----------

QUESTION: the tires are all good on it, or at least that is what they told me when i had them rotated and all that. it has been shaking for awhile now and continues to get worse. there is no noise or shimmy when turning. and like i said it stops after it hits about 15mph and will not do it again until you stop and start to go again

Answer
I still think it's a tire. if you drive though it meanking it slowly goes away after 15 MPH. it can have a shifted belt in a tire and balance okay. that is why road force balancing tires works it will show up a bad tire. Then again if the tires are low on thread depth there isn't much use doing that.