ord Contour jerking, and stalls after warming up

Hello,

Heres the problem im having with the contour. The motor is new in the 95 so thought i would point that out. It drive great up till it warms up, then starts jerking, and stalls.... I was told it could be the trans went bad ( Which what i know about cars i do not think) or a senser went bad on the trans. A buddy of main ad the same problem with a Chevy car, and replaced a $15-40 senser. I also thought maybe the trans filter might cause this, but not sure.

Thought i would see what you guys thought be for i start tearing into it myself.

Thanks.