Ok, I know these trannis have a problem with grinding gears, but I noticed tonight that everytime I shift from 3rd to 4rd hard, it grinds. It doesn't matter how long I've been driving it. Am I just never supposed to shift hard from 3rd to 4th? When I have my work done at MD, I'm going to have the tranni fluid changed to royal purple ATF. Will that help? I hope so, because this sucks.