I think it is transmission problem, it doesn't down shift when it is cold its stock in the 3rd or 4th gear when I am going 10mph. I go to neutral and the engine revs up with no hesitation but he auto transmission won't down shift. This only happens for the first 5min after the cold start and its fine after that. Is transmission fluid need to be warmed up before it can work properly, Any ideas what to do? thanks