I have the A442F fully hydro auto tranny in my 1990 HDJ80. When the tranny is cold it doesn't want to shift up gears while in D, but it will shift when I run through them manually using the shifter. After it warms up for a minute or two this goes away and it shifts just fine for hours on end. Does anyone have a clue what the problem might be? I'm curious if a valve body upgrade might fix this but Rodney's folks haven't been remotely helpful in figuring out my actual problem.