Hello everyone, I have a 1987 Oldsmobile Custom Cruiser with 110,000 miles on it and I am having a transmission shifting problem. When the transmission is cold the car shifts great, however after the transmission heats up the car does not want to downshift. Usually when this happens the car stalls and will start back up and continue this way. I've noticed that it does this more often on days when the weather is 70 degrees or higher. When the weather is below 60 degrees it rarely has this problem. I have had the transmission fluid replaced with the filter and both were in great shape/color. I have also taken it to a few transmission shops and have been told the transmission needs a rebuild without even looking at the car or test driving it or checking the TV cable. What could be causing this issue? I would greatly appreciate any help. Thank You