'94 3sp trans works better in rain

Today as I was test driving this one, it started out working close to ok! No whine noise, shifting into 2nd and taking off with full torque! Few days ago it was not shifting into 2nd until driven aprox.5mi.,would only go 20-25mph. Today as I drove more, the shifts deteriorated sorta, sometimes it needed to go into neutral after stop to take off with full power/torque, some 2nd gear shifts jumped out & back in and the whine sound came back, will whine in park as gas is bliped. I read about the ground stap fiasco one friend here went through. Just the whine sound bugs me. Going to renew the ground then see if there's still a problem. Is 7176 fluid still available? Or just go with ATF3? 94 reg caravan 3L v6 124k mi.

The 3 speed is a hydraulic unit with the only electronics being the lockup of the torque converter that is controlled by the computer . A ground strap would do nothing on the 3 speed . If its a 3 speed its mechanical problems ....