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Phantom suspension clunk

Two years ago, my 1990 Grand Caravan developed a clunk from the right front wheel area. It was usually a single clunk, though sometimes it repeated a once or twice. The sound suggests something related to frame or suspension. It happened when the vehicle was moving and abruptly leaned to one side like when one front wheel either drops or raises due to a bump, pothole, or when crossing something like a curb cutout like at a driveway or a parking lot entrance where one wheel raised before the other and the car pitched to one side. It happened in my driveway, a bumpy gravel affair where the car leans back and forth in a few spots. The key is the lean when one wheel went up and the other down relative to the body. It did NOT happen when both wheels encountered any bump at the same time, like a speed bump.

It seemed likely to me that it was related to the sway bar, but replacing the bushings had no effect. A year ago I had a good specialty shop, too far from here to go back, replace control arm bushings (which it needed anyway) and then align the front end. After that the clunk was gone.

Last week, I had to replace a u-joint on the right side intermediate shaft, so needed to pull the right axle. To get the control arm down far enough to re-insert the ball joint stub, I loosened the sway bar clamps in order to reduce the spring effect. (Both wheels were off the ground).

When I got it all buttoned up and took a drive, the clunk returned.

All I had done was loosen the sway bar clamps and lever the control arm down with a long bar. I’ve since removed the sway bar entirely and heard no clunk, so the sway bar is evidently part of the explanation, but how? I mean, a sway bar is a pretty simple device, what can go wrong? I can’t visually see a problem with the ends bumping into anything where they should not touch, but maybe I’m not seeing a contact. I can’t say for sure, but I don’t think the bar moved to one side when I loosened it, or when I removed and replaced it. The bushings appear fine. There is some residual oil on the bushings, the result of a leaky crank seal that was just replaced, but I can’t see how that would cause a clunk. The control arm bushings have maybe 10,000 miles, the bearing assembly has maybe 15,000. The car is closing in on 300,000, and otherwise running beautifully. OK, so the car isn’t so beautiful to begin with…it’s a “woodie”. (That wasn’t my preference, but when I bought it, it had a brand new transmission, that clinched the sale).

I’m stumped. Has anyone got any suggestions about what I might be missing? Many thanks to anyone who chimes in!