is it common for the trans to jump or jerk once in a great while

Possibly caused by engine misfire, which is more likely to occur after shifting into the higher gears as then the engine load also increases .. Until the symptom becomes more pronounced, it will be very difficult for 'anyone' to successfully diagnose! .. Engine misfire is often mistaken for transmission problems and vice versa... IF an 'experenced' mechanic can test drive while problem is present > or trouble codes are stored, that would be a BIG advantage!