One problem related to engine knocking noise has been reported for the 2009 Toyota Highlander. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 Toyota Highlander based on all problems reported for the 2009 Highlander.
March 10, 2016 vehicle was taken to dealer for oil change. Parked vehicle after return home (10 miles drive between dealership and home) same day and after a few hours, noticed all oil had leaked from vehicle. Vehicle was towed back to dealer that day. Upon investigation dealer said the problem was the oil cooler pipe. Dealer said Toyota issued a technical service bulletin t-sb-0201-11 over 5 years prior that issued a repair procedure to replace this oil cooler pipe. Dealer replaced oil cooler pipe under warranty per technical service bulletin and assured me that no damage to the engine was "apparent" after the repair. July 18, 2016 returned to same dealer for a problem with the engine making a loud knocking sound upon fast acceleration. Dealer diagnosed problem as a rod knock and confirmed it was due to the oil cooler pipe leak from March. The repair involves replacing the engine an extensive and very expensive repair. Toyota needs to make this technical service bulletin problem a recall to avoid unnecessary engine damage and potential safety hazard to the 533500 estimated vehicles included in the bulletin.