Shock Absorber
WARNING: This page is about a different car, the 2004 Toyota Highlander, 2003 Toyota Highlander, and 2002 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.
Compress and extend the shock absorber rod and check that there is no abnormal resistance or unusual sound during operation. If there is any abnormality, replace the shock absorber with a new one.