had a great experience purchasing a Denali but the...

had a great experience purchasing a Denali but their service department is horrible my suv had shifting issues the first week they said it was a reprogramming update (false) then i had bought really nice 26 inch black wheel they called saying they ruined a tire and wheel (false) again it was two wheels and tires left front and right rear how does that happen (drive .throughs) somebody went to lunch in our car. i had decided to possibly trade in vehicle for an escalade but took it into service department first because of a faulty mirror and faulty tv at 36k miles. They said i was over warranty by almost no miles and that i had to pay in order to get it repaired.