Our new 2017 Holden Colorado LTZ auto has a vibration between 90-105 km/h. It’s been back to the dealer twice. I was told low tyre pressures, but they were checked and were right before it was taken to the dealer, I was told the rear view mirror was loose, it wasn’t. I feel I’ve bought a lemon. From my experience, I believe the torque converter is the problem.
Who can properly diagnose new car fault?