1997 Jeep Grand Cherokee Trans problem

I have a difficult Transmission problem it seems. My ignition will not flash me a code on the o/d light on the dash. My check engine light comes on and will only give a generic trans problem code with out being specific. I was told that by AAMCO.

The problem? Well, when highway driving for about 10 miles and then running into stop and go traffic and traffic lights, the engine revs up to over 4 grand before it will shift from 1st to 2nd. Soo, after a few more stops, it wont shift out of 2nd until I am going almost 55. The if I put it in neutral and back into drive, it will shift.

At different times during this cycle, it will slip badly until I take it out of gear into neutral and then back in gear. It has been doing this constantly for about a week now. Short trips, no problem, so as it heats up, it goes into this routine. I had the pan dropped and no signs of shavings or any foreign material. Did see a very very small amount of aluminum dust particles.

Any ideas besides an 1800 dollar rebuild? Again it won't give any codes, so Should I eliminate that it is some sort of sensor problem or temp control module?