tranny troubles

I bought a 1991 Grand Am for my son recently. It has 140K and overall runs good. There is a problem with the transmission, though sticking in overdrive. When this happens, and you slow way down or stop the car stalls out. It sometimes disengages quickly, and other times it can take up to an hour (on the side of the road) for it to finally diengage and funtion normally. What is the easiest fix for this dilemma??
Thanxs...Steve

Welcome to the forum. I would say your problem is either related to the TCC or the vacuum solenoid hose, but before you address either issue, I would get a simple tranny fluid drain / fill & filter change. Do NOT get a flush. Just change your fluid and filter, and see if that solves the problem.