Getting a knocking sound in my 2005 ls430. So far i've replaced inner and outer tie rods, lca bushing (figs 90), sway bar bushings and the ball joints. Still getting the knocking sound but sounds like its coming from one side. I don't think its the wheel bearing since its knocking and not rumbling. Let me know what else ya'll think i should check before i do wheel bearings.

 

Is your car stock? You should also check the upper and lower ball joints

 

Check to see if your struts are leaking

 

Im on airlift 3p, but all the suspension components on the front are all stock. The only thing i have yet to change is the upper ball joints.

 

Possibly motor/tranny mount?

 

is the one side its coming from the drivers side? Do you only notice the knocking over bumps or rough roads? Or every time you push the brakes?

 

My indie drove my car extensively and looked it over on the lift with a rubber mallet. He told me the sound I hear is from the brake shims being missing. I have not put them in yet, but I have the kits for front and rear. He duplicated the sound by tapping on the tops of the pads. I can see that there is some natural movement around the pins, and having 2 shims on both sides of the pad backings could do something. It doesn't bother me enough for me to remove the pads and put them in, I'll do it when the pads need replacement (they were new)....

edit p.s. over the phone indie said for sure sway bar end links. But once it was on the lift he said no, they are fine.

 

 

It sounds like its only coming from the drivers side, feel the knocking under my feet while i driving normally between 40-65mph. Different road surfaces cause the sound to be quiet at times and louder on others.

 

Could be the upper control arms, could be the wheel bearings (the two things I haven't done either) I wonder if it isn't the steering shaft u-joints that have gotten some play in them.

I am in a similar situation to you but have decided to live with whatever knock is left. I feel it more in the steering wheel and hear it coming from the wheels. I wouldn't say I really feel it in my feet.

Let us know if end up trying anything and what the results are.

 

So i went to my mechanic today and he said it seems like the front two wheels are bent which is causing the car to have that clunking sound. Car starts to vibrate on the highway from about 65-90 mph and the clunking sound picks up in speed. I mounted the stock wheels couple months back and still had the knocking sound. Definitely is something rotating causing the sound just dont think its just the wheels causing it.

 

Sounds like you need to find a different mechanic to visit...

Bent rims/wheels will not cause a random knocking sound. They will, however cause a bad vibration at speed. It would be consistent regardless of the road conditions. Your installing the stock wheels verified that the wheels were obviously not the problem. I would go back and look at upper control arms or possibly wheel bearings. To me it sounds like a strut problem, but you mentioned that you're on Air suspension, so I'm not sure if they even could cause a knocking sound...

 

Your mechanic is a dirtbag and trying rip you off, bent rims do not cause a knocking sound.