One problem related to suspension noise has been reported for the 2004 Subaru Impreza. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Subaru Impreza based on all problems reported for the 2004 Impreza.
1. At about 12000 miles,the right rear of vehicle began to make a knocking noise while going over bumps,braking or accelerating is more evident at low speeds but is still present at higher velocities. 2. The failure is currently still existent,the right rear of vehicle has about 1/4 in loose play before the rear strut binds. This affects handling of vehicle during turns or emergency maneuvers as the suspension is not well controlled by strut binding. When coming to a stop,one can feel the right rear corner of vehicle settle and hear a knocking sound. This issue twice sent the vehicle out of control while turning to the left on bumpy roads and fortunately no one was injured and no damage was done. This defect has been talked about at great length in various Subaru Impreza sti forums and is referred to as the"rear strut clunk" and it can affects both sides of vehicle. Model year 2004 and 2005 Subaru Impreza sti are involved in this. It is possible that my 2006 and 2007 are as well but I haven't checked. 3. The dealer has replaced the upper strut mount a few times to no avail. The defective parts are still on the vehicle.