My 84 Riv was doing just fine, until a couple of days ago when the transmission suddenly started acting up. I checked the fluid after driving, it was at the bottom of the cross hatch on the dipstick, so I put half a bottle in, still same problem. Fluid is perfectly clean, no problems there. Has about 64K miles. From what I can see, it is OK for about the first 10 minutes or so of driving, and then it starts slipping out of gear and/or not going out of 1st gear. I drove it yesterday, and it seemed to shift from 1st gear to 2nd at about 45mph. But still haven't established whether it does that all the time or not. The only thing for sure right now is that it's fine for about 10 minutes, then starts malfunctioning after that. When I took it out on the highway the other day, it started acting up after I downshifted to pass someone, not sure if that has anything to do with it though. I was looking for the vacuum modulator line, but I can't seem to find it anywhere. Also, does this car have a TV cable like the Ford cars do? There is a 2nd cable under the throttle cable, might be a kickdown don't know.