My question: is your CT5 an 8-speed or 10-speed transmission? The reason I ask is because I also got a CT5 in late July and noticed a sound coming from under the car. I first noticed it at constant slow speed. It continued until the speed changed from either increasing or decreasing the speed. Once I was aware of the sound (more like a helicopter sound, or flapping sound) I was able to hear it at speeds under 60. I took it into the dealer, and the tech was able to hear the sound. He contacted GM engineering. First, they thought it was the plastic shield under the car, so they sent insulation, that didn’t fix it. Next a CT5 on the West Coast had the same sound; it had a bad electronic motor mount. They checked mine which also had the same problem. They replaced it, but that didn’t fix the sound. They then said it was a transmission problem and needed to write new software to fix. I waited but then was told that it was a CHARACTERISTIC of all CT4s and CT5s with a 10-speed transmission. No further action was to be taken on their part.
If nothing else happens, I will be contacting legal advice, as to pursuing The Florida Lemon Law or The Magnuson Moss Warranty Act.
