Rear suspension knock., Searching wasn't helpful. Options

[richee3]

I recently installed TRD coilovers on the Celica to replace the aged stock suspension. The struts weren't totally blown but they weren't great and the springs had to have helper blocks in them, but they were quiet. After lowering, we found that the rear started knocking quite badly. Based on recent threads, I replaced the rear sway bushings with 16 mm with Energy Suspension bushings and the end links with Racing Beat Miata end links. While this cut the knocking down by half, there is still a persistent knock. It only happens at low speeds and seems to be from the right side more than the left, but it isn't strictly on one side or the other. All nuts and bolts have been checked and are confirmed to be tight.

When I searched, the only potential suspects I can find are trailing or control arms or the exhaust hitting the car. I don't believe it's the exhaust since it only happens at low speeds and I've followed the Celica and the exhaust seems stationary. So what are the odds that I need new rear bushings and it didn't become apparent until I was lowered? Anything else I should check? Any help or advice is greatly appreciated.

By the way, I'm intending to replace my rear bushings anyway, I just haven't done it yet. Procrastination is terrible.

[richee3]

Little update, I've got the bushings now, so I'm almost ready to order the last few bits and get started on this. Just to confirm from the diagram on the first page, I will need:

Four of the long bolts that go through the lateral arms (90901-09001, 90901‑19001)
Four nuts (90179-14019)
Washers (90201-14017, 90560-14022)

Anything else I'm not immediately seeing by glancing at the diagram?

It should be noted that my clunking has gotten slightly worse in the past couple of weeks. Not so much that it's clunking more at low speeds, but now the same sound can be heard at higher speeds, more from the left side when I'm going faster. The sound I hear the most sounds as though the nuts that hold the strut in at the top are loose and that it's the strut itself moving around, but I have checked, rechecked, triple checked, and checked them some more. The sound I'm getting is like three or four light knocks, independent of the one big thunk I get when going over bumps. Like the coilover has done its work and the impact is causing something else to knock. I'd get a video but regrettably, it's a noise you just have to be inside the car to hear.

This post has been edited by richee3: Jul 29, 2012 - 4:51 PM