I have a 2001 Jeep Wranger (4cl) automatic that has hated highways. When i drive on the highway, after about 4 hrs, my jeep decides to slip into neutral. So i initially have to hit the gas pedal to make it down shift and then it seems okay but of course after about an hour it does the same thing. Hence a long ride becomes much longer. I usually pull off and let it the engine cool down and that seems to help and i can resume the highway once again. I have had the transmission looked at and a transmission flush done. I have been told that i do not need a transmission but the mechanic has no idea why this occurs. Any help would be most welcomed. thank you!