Okay speaking of front ends....
i have a corolla Axio which has done around 95000 km. When i bought it around two years back, it had done around 40k. Even then when i drove it, i noticed a very very faint "dug dug" sound from the front end while driving over plain roads when the car moved up and down due to changing road level. I am not talking about pot holes or bumps, over which it drives without any noise from the front end.
This sound that im talking about is a very faint one, feels like its coming from the steering column, but the steering has no play whatsoever. It is firm, does not move freely even a millimeter, produces no sound when moved rapidly from left to right.
Over time, this sound has slightly increased but it is still hardly noticeable. But since i have this in my mind, i can hear it.
I have physically inspected the anti roll bar bushings, ball joints, steering link rod, its joints, the lower control arm bushings, and everything apparently looks fine, no grease leakages and no extra movement when pried.
Since there are so many parts in the suspension that could go wrong, i cant possibly change each and every one to see if thats the culprit. So my question is: what is most likely to cause a sound like that from the front end? Steering box? Steering u joint? Antiroll bar? Lower control arm? Shock absorber? Ball joint?! What can it be?