Automatic Stability Control (asc) problems of the 2014 Hyundai Elantra

On 5/30/14 I purchased a 2013 Hyundai Elantra close out with 54 miles on it. At 4300 miles I lost all control of the steering and the car went across 3 lanes of interstate 3 times before I regained control of the car. I returned the car to the dealer and had to "trade it in" to get a different car. I left the dealer with a 2014 Elantra limited on 7/21/14 having to pay them an $4500 extra. The 2014 felt better on the road now at 1300 miles I start felling the same fish tailing feel when the car is going interstate speed 70mph. As I write this the car now has 1944 miles and the condition is getting worse. I drive the same interstate everyday and the road conditions have not changed. I no longer can drive this car interstate speed, I now have to drive it at no more than 55mph. The 2013 did this fish tail or wander also, and just before it went out of control it did it sharply for no reason. Now I have concern this will happen with this car also as the symptoms that are starting are the same. I called Hyundai customer care and filed a complaint, they said they would do what needed to be done to fix this issue. The wobble and unstable feel driving this car, is a very on edge unpleasant ride as one does not know if it will lose control. I do not know if it is the steering or the stability control or even the suspension that is the issue. You can't feel the wobble in the steering wheel, you feel it though out the car. I have now had two Elantra's driven them a combined mileage of 7000 miles in 8 weeks and both have the same issue. Something is very wrong with the control of these cars and there needs to be a recall, I can't be that unlucky to get the only two cars out there with the same issue.