I've been having a knocking sound from my front suspension for a long time now, I had pretty much replaced everything possible but that sound was still there. The other day I noticed that the sound was being made when the stabilizer bar moved up and down in the rubber bushings. Those bushings looked OK but I replaced them anyway. It fixed the noise. What was happening is that even though the bushings were still round and not "bad" looking, the lubricating material within the rubber was gone and the bar was sticking as it tried to turn. I noticed the new bushings had this white waxy stuff impregnated in the rubber that apparently is there to provide some lubrication. That was looong gone in the old bushings.
The bushing replacement went OK until the last of four bolts, that one (of course) snapped off at the head. There was NO (I repeat, NO) clearance to drill it out, so I had to drill an angled hole through the top of the frame and then another hole through the bottom. I then used a long grade-8 bolt to hold the bushing clamp in place. The only way to drill out the broken fastener would have have been to drop the sub-frame and I was NOT in the mood for that.
Anyway, just a heads-up in case you think a bushing looks ok it still might be bad.
The bushing replacement went OK until the last of four bolts, that one (of course) snapped off at the head. There was NO (I repeat, NO) clearance to drill it out, so I had to drill an angled hole through the top of the frame and then another hole through the bottom. I then used a long grade-8 bolt to hold the bushing clamp in place. The only way to drill out the broken fastener would have have been to drop the sub-frame and I was NOT in the mood for that.
Anyway, just a heads-up in case you think a bushing looks ok it still might be bad.