Got new tires on my 2015 Enclave with just 34,500 miles on it due to an unrepairable flat tire. After spending about $850.xx I also got a 4 wheel alignment (after a huge investment). The new tires are same size spec, but I went with Perelli Scorpion Verdes all season. But ever since I have had issues with the ride (can not inflate these tires more than 32psi cold, or the truck rides like a 50 year old wooden Rollercoaster). Secondly I have had the tires balanced 3 times since install in less than 1000 miles of driving because the E and steering wheel is smooth as usual.... except between 62 and 80mph (the steering wheel shakes and shimmy. I can also feel vibration in the gas peddle and my seat). At 60 and over 80 everything is smooth as glass. What's wrong!! I just want my Enclave back to the way it was. HELP!!