Update, replaced the steering rack bush yesterday and it did eliminate some sound but the 'kuk/tuk' sound becomes more apparent. My mech was surprised and further check revealed that the front subframe bush is torn. When we replace the steering rack it made it worst as the bush is torn and all other bush are in great shape. How to repplace? 1.remove everything connected to the front subframe (lower arm, etc) 2.remove the subframe. 3.send it to machine shop to press the bush out the press new bush in. 4.reinstall. Still planning for that as might as well to replace all the 4 bush on the frame while its removed.