One problem related to automatic transmission has been reported for the 2004 Subaru Outback. The most recently reported issues are listed below.
Auto started running rough. Transmission shifting abruptly. Throttle would remain open after foot taken off accelerator. Car would maintain last speed before foot off accelerator. This would continue on level ground and even uphill to a large extent speed would be maintained with no input from driver. Cruise control was off. No codes generated and no check enging light. Dealer notified. Could not duplicate. This occurred on three separate occasions before dealer replace throttle positon sensor.