I am desperate, I bought a 2017 L405 SD V8, it came with a few issues but one I cannot cure. Suspension noise on anything but a perfectly flat road. Knocking front and rear. I have replaced both front struts with genuine parts both bottom arms, front and rear drop links. Front and rear anti roll bar bushes. What is the noise? It’s driving me mad. If you are not part of the solution you are part of the problem!!

How many miles on your truck? My guess would be lower control arms. If the mileage is on the higher side and they haven’t been done, it’s probably worth it just to do them in my opinion. If they aren’t the main source of clunk, they are probably next.

Have you replaced the antiroll bar drop links? The wear on these can be very difficult to spot, and can cause an irritating knocking when worn. They are a relatively cheap fix to try.

Agreed. It sounds like he may have already replaced these, and possibly even the LCA’s. My next thought would be motor mounts, but that’s a quick $500+ US. At this point, it might be best to just bring it somewhere for a diagnosis before continuing to drop more money into it. I have not heard about people experiencing a rear clunk too often, so not sure if something more is going on.

I had a very similar issue with my MY17 that I chased for 8 months and visited a number of garages to finally cure.

It turned out to be the dogshit quality ARB bushes/links I used (Febi Bilstein) they simply were not up to the job. What brand did you have fitted?