Kestas, thanks for the suggestion. I did change the fluid after all. The top seems to work better in all modes except for the one I was trying to repair .

I have noticed I can slow the rate of fall of the back panel of the roof by quickly activating and deactivating the switch during that mode. I don't know if any of the convertible/hydraulic "gurus" out there are clued by this observation, but it seems worth a shot. Thanks all.