purchased a 2020 silverado LT 2.7, ran great getting 24 mpg , live in Iowa so cold mornings, started it yesterday morning both radiator fans were blasting at full speed. after pushing the start button and put in gear the ywent back to normal. This morning i started the vehcle and it did the same but this time when i tried t odrive it noticed the oil pressure at 90psi and after driving approx 10 miles no heat, the truck never got any heat and the mileage was at 14. Called the Chevy dealer and told them to come and get it. No iidea what is causing this issue. has less than 800 miles