eplur, great job of standing up for yourself. If there is a problem with one or more tires or wheels (unlikely to be all four) then a competent tech on a road force balancing machine can find it. Two requirements there...first, the machine that detects road force variations, and second, the tech that knows how to run it properly.
Here is a very informative article about tire vibration causes: http://www.tirereview.com/when-is-it-overkill/
Here's the machine that's needed: https://www.hunter.com/wheel-balancers/road-force-elite
This is the newest machine that does the job more quickly and does more for the tech. Older version do a fine job, but require more knowledge from the operator.
In all these cases, we need to stop talking about balance. Rebalancing a tire with a different problem yields the same vibration. Just talk about vibration. Their can be several causes of vibration other than balance.
Don't forget your big gun--the Lemon Law. Here's New Jersey's version: " The defect must substantially impair the use, value or safety of the vehicle or be a serious safety defect which is likely to cause death or serious bodily injury if the vehicle is driven." eplur's experience seems to qualify here. I'm not suggesting that he file to have his car bought back, 'cuz now it's fixed, but just the threat of a Lemon Law claim should get the dealership and the manufacturer regional rep off their butts. Each state has their own version of a Lemon Law, so if needed, check your state's version. (My state has a wrinkle--it only applies to cars bought in-state. That maybe be a consideration.)
Here is a very informative article about tire vibration causes: http://www.tirereview.com/when-is-it-overkill/
Here's the machine that's needed: https://www.hunter.com/wheel-balancers/road-force-elite
This is the newest machine that does the job more quickly and does more for the tech. Older version do a fine job, but require more knowledge from the operator.
In all these cases, we need to stop talking about balance. Rebalancing a tire with a different problem yields the same vibration. Just talk about vibration. Their can be several causes of vibration other than balance.
Don't forget your big gun--the Lemon Law. Here's New Jersey's version: " The defect must substantially impair the use, value or safety of the vehicle or be a serious safety defect which is likely to cause death or serious bodily injury if the vehicle is driven." eplur's experience seems to qualify here. I'm not suggesting that he file to have his car bought back, 'cuz now it's fixed, but just the threat of a Lemon Law claim should get the dealership and the manufacturer regional rep off their butts. Each state has their own version of a Lemon Law, so if needed, check your state's version. (My state has a wrinkle--it only applies to cars bought in-state. That maybe be a consideration.)