2017 ILX just installed new struts, links and ball joints - knocking noise
 

First time doing a suspension repair on my ILX. Passenger side strut was destroyed along with the ball joint. Both sides had loose sway bar links. I ordered parts for both sides (went with FCS quick struts from Rock) and installed. Had a hell of a time with the end links and could not get them off without heating and on the passenger side I had to cut them off. That was a pain. Anyway, I noticed a couple things when I was done. First impression was fine, and then I noticed it started knocking a ton when I was driving at lower speeds. Everything appeared tight. But- I didn’t tighten the sway bar links under load. I didn’t have an offset wrench so I just impacted them on, which I now think they’re truly not tight. I brought it to get an alignment and asked them to check if they were tight - they said they tightened the passenger side but the left side was stripped and they couldn’t get it out without cutting it.

I re-ordered new links; went with Moog this time. But something else that was off: the bolts at the top of the struts were longer than the factory ones, so the plastic caps won’t go back on without popping off. I’m not concerned about the caps, but it’s more a question of was there supposed to be a mounting bracket or something before it mounted to the body? The ones I pulled out didn’t. The only thing I replaced from the original was the little plastic/rubber cap over the center bolt. The mounting bolts did look a little longer on a side by side comparison.

I can replicate the clunking myself if I steer back and forth while driving at a slower speed. So this leads me to thinking it’s just the sway bar links… but for any other amateurs that did this job and had noise, is this accurate you think?

None of what you replaced really needs to be tightened under load. It's just control arms and this is more of a factor on double wishbone suspensions vs mcpherson strut setups.

Tbh my first thought is a defective strut mount on those FCS quik struts. FCS is a value/economy brand not quality.

Get the front wheels off the ground (=weight off the struts) and turn the wheel, does the clunking go away?