I've done some searching about this issue and come up with so many answers, just want to see if any TL owners have some ideas. I have an 08 type S, change the shocks for koni str's and eibach prokit. I have a clunk from the rear left over low speed bumps. I changed the end links and rear sway back bushings, even swapped the rear left shock....clunk is still there. Please help me figure this out.

 

Anyone?

 

As you stated there could be a number of reasons. With the number of parts you replaced I would first check and see if anything is loose. I had a clunk in the rear of my car and turned out the top nut for the shock was loose.

 

Starting to hear a similar noise on the front right. Checked the top nut on all 4 corners, rears were tight and didn't move when i tightened them. On the front i was able to do a half turn to tighten both. The noise is still there...

 

It is really hard to diagnose noises without hearing them in person. Could be ball joints, shocks, or sway bar end links. You stated you changed the shocks and end links so possibly a ball joint. The compliance bushing is also a common problem with our suspensions so you might want to check on that for extreme cracking and weathering. Hope this helps

 

So it started after the Koni's were installed? Were they brand new?
Do you have the option of going back to stock suspension, to see if the noise goes away?

 

Started after the koni and eiback pro kit, all new. No option of going back to stock. Today i changed the strut mount bushings, the noise is still there but not as loud.

 

so, this past Saturday was warm and the clunk went away...Sunday was not as warm, clunk was back. I'm starting to think it's surely the shocks.

 

If you have custom springs, make sure the closer rings are not collapsing on itself without a spring insulator . Inspect it while under a load and see if they are too close.

replacing swaybar links did nothing for me.

I got better results by removing konis. I threw mine in the trash. I now have eibach and kyb and it rides and handles as good as a lowered TL can get. As far as comfort is concerned.

I think in general when bushings get old, they get harder. And any time you take out rubber bushings and replace with solid parts, like for racing, noise goes through the roof. I did that on my camaro once and it lasted 5 miles. So, I think these cars need a full bushing replacement on the front and rear subframes. Also on the front, compliance bushings should be replaced. I don't like these suspensions. Too many components.

the front is another topic. I got the noise down to a minimum but still not 100% like it was when my car had 35k miles on it. On the front, I have replaced inner and outer tie rods, lower ball joint, upper ball joint arm, bearings, brakes, shocks, sway bar links... the only thing I have not done is compliance bushings.

I installed a rubber insulator on all 4 corners between the top hat's and the body. It also helped.. I think..

 

Update: Got rid of the Koni's and that solved the problem; also the rears were blown.

 

Awesome. Mine started making noise 2 weeks after I got them. And mine were never firmer than 1/4 way up from the softest setting. And I live in Dallas., where roads are pretty good. So, no reason for them to fail. Interestingly, these TL's still develop noises over time, but they do not need any extra help from Koni. haha