I am hoping I can get your input on the most likely source of a very rare, but very loud clunk I have gotten twice on an 02 S60 2.4T AWD (142k miles) that I got two and a half months ago. The first clunk occurred 3 weeks after I got it. It happened when I went over a raised section of road almost like a speed bump going about 20-25 mph. The loud clunk almost sounded like I hit something big and metal against something big and metal in the engine compartment, really hard; I was ready to stop just ahead get out of the car to make sure nothing fell out! Pretty certain it was just a clunk I kept going. Went over a few potholes here and there and could not reproduce it. Seven weeks go by with a nice smooth ride and no sounds, before I had the second clunk happen yesterday, after pulling out hard out of a parking lot that had somewhat of a v-shaped dip between it and the road I was pulling out onto. The sound was very loud, metal on metal. Very scary since I can imagine the force behind that sound reasonably resulting in damage.

Has anyone experienced this? Any ideas what this could be?

 

spring seats?

 

My independent mechanic inspected the suspension and all bushings and mounts twice, once before I bought the car, and then a second time because of this, and the only thing he could find was a worn front swaybar endlink on the front passenger side. I replaced both, and that did not fix the problem. My local Volvo dealer also did an inspection of the suspension components before I had them perform an alignment, and they did not find anything wrong.

Ball joints, tierod ends, control arms, struts, mounts, etc. all have zero play and are are in excellent condition. The struts are tight and do not bounce whatsoever, and the mounts did not give the appearance of having any problem or have any play or make any sounds when the struts are compressed. I have also tested the strut mounts by turning the 21 mm top nut clockwise and they are under a lot of tension; I only get maybe 1° of rotation before they squeak back to starting position. The sound does not appear be coming from the struts, so I do not think this is suspension crash of any sort. It almost sounds like a major component is loose, and is hitting another major component only when jostled hard.

Since someone suggested it might be the right motor mount, I removed the wheel and part of the wheel well to get a good look at the right mount. I was hoping with the better viewing angle than when it was up on a lift at my mechanic and Volvo, I might actually find it to be in bad shape. Unfortunately, after much poking and prodding, it indeed appears to be in good very condition and it was definitely not collapsed.

When I mentioned to my independent mechanic that replacing the swaybar endlinks did not fix the problem, and that several forum members have suggested it might be the strut mount or spring seats, he says it is more likely the strut itself. Before checking the right mount, I stopped at Volvo to pick up some pop rivets (just in case I needed them to remove the wheel well), and I asked the service manager there what she thought. She has been there a long time and knows these cars inside and out. Without mentioning to her what my independent mechanic thought, she also thought in all likelihood it is the strut bottoming out, not the strut mount. She advised that even if I were to replace the struts and it were to fix the problem, in all likelihood, the new strut could start doing the same in 5k miles. So, she didn't think there was any point in replacing them unless it were to become worse. My only problem with this suggestion that it is the strut is that it is currently doing an excellent job damping the road under normal conditions and when the front end is compressed it is stiff to compress and returns back with zero bounce.

This clunk has only happened four times with daily driving the last four months, and the last time it only happened because I intentionally did not slow down for a bump to see if I could reproduce it after replacing the swayer endlinks. It does not happen with pot holes or a lot of road insults. It only happens with speed bumps or the like. With careful driving, I can probably avoid it altogether, but it sucks knowing it can happen at any moment, and I am very concerned of whatever is causing this clunk causing severe damage, as the clunk itself sounds severe.

I am open to any other suggestions. Two other symptoms that might be related is that the car pulls to the right after I take my hands off the steering wheel, after having had an alignment done and then double-checked at Volvo. Also, I have a rubbing sound coming from the steering wheel when I turn it 70° or so. However, I get no clunks when turning the wheel full lock in either direction when in Park, and the steering wheel turns freely.

TIA