Hello to all. 3 weeks ago I started to notice a vibration in the steering wheel. I took it to my gmc dealer and they performed a 4 wheel alignment. After leaving the gmc dealer I noticed that I still have the issue so I went to my buddys tire shop and had all 4 tires rebalanced. I still have the issue but what I have been noticing is that when the trans temp gets around 165 and in overdrive I get the shutter effect. As soon as I put it in 7th gear the shutter goes away. I have a 2016 gmc sierra 6.2 liter with 38000 miles. I just called the dealer and explained what Im seeing and they said they never heard it before. I have a appointment with the dealer this coming saturday. Any hel or info before I go to the dealership I would appreciate it. Also I do not get a check engine light. Also It only happens at speeds of 55 to 75mph.