91 sable

i recently bought a 91 sable i drove it for maybe 3 miles stopped at a red light and when the light turned green the motor was still running but the car wouldnt move it would rev up but not move it was in gear i tried all the gears ... would it be the tranny ? and if so i heard that a ford taurus was interchangeable could i find a used trany from a taurus and have that put in ???? thanks.....