Clunk when shimmying Steering Wheel

[stocker]

I recently noticed that, if I'm stopped and I shimmy the steering wheel back and forth there is a clunk I can hear in the center of the car in the driver's footwell area. I can also feel it knock in the steering wheel and also the driver's side wheel and tie rod.

I already replaced both outer tie rods because one of them had a torn seal. I couldn't feel any significant play after doing both outers so I did not proceed with the inners.

I'm going to have an alignment shop try to diagnose the problem but I'd like to know what I can expect before I go in this evening. I would do inner tie rods but beyond that I'd probably have a shop do the work. Does anyone have any thoughts on what this could be?

2008 grand prix base model
95k miles

[FordMan77]

Check the inner tie rods, rack mount bushings, swaybar bushings, and maybe the intermediate steering shaft. Heck, put it on a set of jackstands and have someone turn it lock to lock and see if you hear/see anything moving/clunking that shouldn't be. Might be easy to spot.

[Fivefingerdeathpunch]

I wanna say intermediate steering shaft, just a guess.

[stocker]

Thanks for the input guys. The shop I took it to said they attributed it to worn front strut mounts (the upper bushing/bearing) as they couldn't find anything else. They mentioned, with the hood open they could see them moving and twisting as the steering wheel was turned back and forth which I was able to replicate when I got home. I don't know if this is normal or not...

Although I think the shop was trying to be honest, I don't think they are right. I can feel the clunking very lightly on the top of the strut mount and the coil spring but the clunk is much stronger when I just rest my hand on the tire treads or the inner tie rod. Also from the inside of the car, the clunk doesn't sound like its coming from the top of the strut.

How can I check the rack mount bushings, and the intermediate steering shaft? I'm not very familiar with these two.

Thanks!

[stocker]

UPDATE:

I have replaced the outer control arms and had an alignment done. The car drives ok but it seems to jump around a little bit when I hit expansion joints or bumps at highway speeds. Sometimes it seems like I jump left or right a bit.

So after trying to ignore the clunking at stop condition (described above) I've noticed over low speed (15-30mph) bumps and potholes I'm getting a decent clunk in the front end. Armed with the previous shop's theory that I've got worn front strut mounts - I'm reassessing my situation. At a stop and I could definitely feel vibration/clunk/knock in the coil spring as I held one hand on the spring and turned the wheel with the other. As one shop noticed, with the hood open, when turning the wheels back and forth the top of the strut mount is definitely moving around and twisting a bit.

So I've got a few questions:

How much visible movement is normal when watching the strut mount?

What can a worn strut mount sounds like?

Any additional test I can do to determine if the strut mount is my culprit?

If the mount are bad my route will likely be to have a shop assemble new front strut/spring assembly so I can drop and swap quickly, all new strut mounts/bushings etc, control arms and maybe inner tie rods. Are these all the parts I'd need to achieve the shop assembly of a front quick strut?

http://www.rockauto.com/catalog/more...109&cc=1440276 - Coil springs

http://www.rockauto.com/catalog/more...078&cc=1440276 - KYB Front Strut

http://www.rockauto.com/catalog/more...410&cc=1440276 - Front; Mount, Spring Seat, Bearing and Retainers

I see the standard ACDelco is a 2 year warranty for about $40 more, are they that much better than the KYBs? This is not a job I want to do often.

Any clarification on what the shop would need to do the assembly would be great. I'm a bit confused by coil insulator, coil seat, strut bearing and strut mount.

Thanks for any input!