Phil[/QUOTE],
You seem to be knowledgable of the 5hp24 trans. My '03 4.6is has a throttle oscillation at constant speed under 62 mph. It feels like the torque converter locking/unlocking/locking/unlocking every 2 seconds or so. This only happens under light constant throttle between 1200 and 2100 rpm. When in cruise, no oscillation. When in Sport mode, no oscillation. 2-1 downshift in Sport mode is a little harsh, but seemless in regular D. No other symptoms, no codes. Dinan trans software installed.

Does this sound like a LUC solenoid issue? If the TC can be commanded to lock up when in cruise or Sport mode, seems like the TC is working normally and more like a valvebody solenoid issue. Any comments appreciated. 141k miles with no history.