The symptoms are such:
Cold engine: Flares for first shift only (2-3). All other shifts are fine. Must ease up on throttle for smooth shift.
Warm engine (40 deg C): All shifts OK.
There is no in-between. Either it slips or it doesn't. I've tried it where the temp is just below 40 and it slips, pull over, wait a moment only, temp now at 40 and shift is OK. This is repeatable 100% of the time.
The tech said it was the seals in the modulator. The modulator is where the vacuum hose connects, right?
I can't tell the color, although the black piece where the vacuum hose connects has a green mark on it. I think my modulator is supposed to be brown, which is the expensive one of course.