Hello everyone! I am brand new to the forum and I'm sorry for the long post. I really need some advice. Last Friday, I purchased my first Hyundai, a 2015 Sonata Sport with 40k miles and I absolutely love it. I have a 1.5 year old baby and my wife and I have been driving a Prius and a Civic for some time, up until now. Needless to say, it's very nice for us to have a Midsize sedan. One issue though. Soon after buying it, I noticed we were getting a vibration that started around 55 mph and then tapered only to come back around 70-75. It seems to taper off again around 80, but I don't want to go any faster for obvious reasons. The vibration itself isn't pronounced at all. It is actually very mild, but it's there for sure and my wife could feel it too. No baby in the car when testing this, FYI. I did bring it in to a garage to have it diagnosed and the mechanic that drove it pointed out a few spots inside the wheels where balancing weights had been affixed, but weren't there. He could have done the balancing there, but said it would be better to get road force balancing done so I went to Discount Tire and had all 4 wheels balanced. The vibration got even less noticeable, except right around 55 mph. Definitely still there and here's the kicker. I bought this car from Carvana and I have until Friday to decide if I don't want it and get a different vehicle. It is still under Carvana's and Hyundai's warranties and I'm going to bring it to a Hyundai dealer tomorrow for testing. I really don't want to return the car. I like it a lot and so does my wife, but I also want to make sure we bought a good car for our family. Two questions, for those of you who made it to the end of this novel, what could be causing the vibration and should I try to work it out or just go for another car? Thanks for reading. I'm sorry it was so long.