kinggrimwo

For a couple years the SC4 shifted rough into gear, and sometimes rough between gears. Never seemed worse, and on different days seemed to have no problem at all.
After driving a few hours on the freeway today i got back into town, and as soon as i was in the stop and go mode the transmission started slipping out of gear. Not a few miles later it was immobile.
What would cause it to just go out like this? I was thinking maybe it was a fluid pump or something. As it is now, when i turn on the car it will go into gear for a few seconds and you can probably go fifty feet before pulling over again. I'm not attempting to drive it until i get it fixed.

Looking for diagnostics and possible repair costs.