Originally Posted by dinan e39

Just when I thought I had escaped a faulty tranny, problems are now rearing their ugly heads. The car is a 2005, 4.4, 57K miles with updated tranny software. The symptom is as follows: Driving on flat roads around 30-35 mph at roughly 1000-1200 rpm, the transmission jerks as if it is attempting to shift. The jerk is very quick almost like the motor is missing. As soon as you apply a little throttle it goes away. I haven't completely ruled out the motor but it feels as if it is generated from the middle of the car. Any others have this happen? Any diagnosis? TIA.