Hi all, I have a 2011 Chevy Malibu LT 4 door with 100,000 miles with a 6 speed automatic tranny. My problem is the tranny is fine in the beginning shifts no issues all gears, but when the car is gets warmed up its like it shifts into neutral. I can wait a few minutes and drive again till it warms up again. Do I need a whole new transmission or could it be a modular issue. Thanks