What could cause 90% loss of acceleration and extreme vibration accelerating?

What is your question?

I have a 95 oldsmobile supreme with 52k mile. It has a rebuilt transmission with only 7k miles on it. On a interstate drive home from school, the rpms dipped a couple times but with no real discernible effects. When almost home, I turned onto a side road going up a incline, and the car`s acceleration dropped to nearly non existent ( struggling up a small hill at 20 mph, momentum carried me most of it ) and it started shaking bad enough it felt like my front tires had gone totally flat. Almost home, I kept going, and when I let off the acceleration the problem stopped, then after a short period of normal acceleration, did the same thing. It continued bad enough the next day I had it towed instead. My shop looked things over, it did the same thing to him, diagnosis was a likely transmission problem. Had it towed to trans shop ( under warranty ) and the problem had stopped by next day when he looked at it. I fueled up on way home before it started. Used fuel stabilizer after problems

What makes this problem better or worse?

Unknown

How long has your 1995 Oldsmobile Cutlass Supreme had this problem?

A week