2001 GP GT clunking over bumps

[meggabad]

My wifes 2001 GP has this clunking noise going over bumps or variations in the road. I replaced the strut on that side (drivers/left) and did nothing to solve it. I was wondering if anyone had any ideas or is this a common problem with this car. I searched and didnt find anyone with similiar problems. I do not feel it in the sterring wheel, in fact that feels solid still. No whining or grinding, just sounds like metal slapping/rattling when going over bumps. Any help would be greatly appreciated!

[T_ravis]

I recently had a similar issue with my 2002 Grand Prix GT. The first issue I found was the sway bar cracked and was popping on right hand turns. So I replaced and the noise went away for a month or so. After that I started getting a clunking noise on bumps and had a shop replace the inner tie rod. A few months later the noise came back and the shop said I needed struts. I found the forum and the procedure for struts and replaced both myself. But when I went to get the alignment the noise was back. A member on the forum suggested I shake the tires at both 12 and 6 and 9 and 3 to see if there was play in it. I believe 12 and 6 is for the control arm and 9 and 3 was the tie rod. I didn’t notice any play so I had a new shop look at it and he suggested it was the tie rod the other shop replaced. He believed it was a low end cheap part. So with the car nearing 100k I decided that I would replace both sides control arms and inner tie rods. When I got the inner tie rods and control arm off I noticed that both ends had allot of play in them and needed replaced. After that I haven’t had a clunking noise on bumps or turns. Lastly I would recommend doing it all at once. I had a shop initially do one part which fixed it temporarily and the other side went bad right after causing me to pay for multiple alignments which added fast. Replacing the parts is extremely easy and can be done in a couple hours if you chose to go that route. Good luck

[meggabad]

Thanks for the info, I really appreciate it. I replaced both struts with redi-mounts and while doing so noticed that in fact the sway was cracked all the way around one end. So i replaced that as well with kit including all bushings. This car has only 70k on it, and everything else in terms of lower control arm bushings look great. the noise still exists, however the car rides so much smoother with the new struts the it isnt nearly as noticeable, in fact, they probably eliminated 90% of the noise. I'm going to really inspect the underside today to see if there might be something else making the noise like a exhaust clamp or loose heat shield or something. The steering and everything else on this car is so solid, I'm leaning towards something other than suspension related. I'll report back on my findings, thanks again for all the info.

[meggabad]

I finally figured out what this noise is coming from. It is coming from the catalytic converter. I never suspected this because we just had it replaced at the dealer under GM's extended warranty for Cat Converters for this year of car. Apparently they put one on it that was worse, or could have been due to the poor suspension broke part of it loose inside the casing. Anyway, car rides like a dream again with the new struts and sway bar, so I'm happy.