2007 Gen 2 - XLT 2 Wheel Drive - 193k miles So the past week, I get it started, put it in reverse, and there's a hesitation before the truck engages in backing up. And a similar delay when I shift it back to drive. I've drove this 120k miles, and never had to touch the transmission on it. Should I get a flush/fluid change scheduled? Or is this indicative of a bigger issue?