Today I was driving to school in my 1996 Jeep Grand Cherokee and noticed a slight problem. The transmission would shift smoothly into 4th gear, around 45-50mph where it normally does, but the tachometer would rev upwards by around 300-400rpms and I noticed a slight jerk, only very subtle. This happened twice to me on the way to school and also twice again on the way home. Most of the time it would shift fine and stay at a normal RPM but sometimes it would do this. The problem only occurred when the truck had been running for a while. I had the fluid changed and bands adjusted around 125K because of the bump-shift problem. I now have 142,500 miles and also run a 3" suspension lift with 31 inch tires. I have gone off-roading quite frequently but maintain the vehicle fairly well. If I hadn't been looking at the tachometer, I don't think I would have really noticed the problem because the jerk is very subtle. Does anyone have any input on what this problem could be? Also, I checked the trans. fluid and it was light pink, full, and smelled normal. I can't really afford the time or money for a transmission rebuild so hopefully someone can shed some light on whether this is a major problem or just something simple.