NHTSA Complaint #11700441 — 2023 CADILLAC XT5

The car has a shudder/vibrate and what feels like jerking at certain speeds. I have a 2023 XT5 Premium Luxury 3.6 However, I have taken multiple times to Big O tires had tires replaced, brakes, Lower control arms, I still had a vibration issue. Took back to Big O due to Tire balance issue but came back tires and balance and alignment were fine. I was told that Big O, hooked the car up to a TPS machine and stated my torque convertor needs replaced. My car only has 51,500 miles. They stated that the shudder is between gears 3 & 4. I understand my car powertrain and drive train are under the 70,000 mile warranty. But I keep hearing this is major issue with the 2023 XT5. Making me think I have a lemon since the issue is already happening on such a new car.