I've read some posts concerning "mushrooming" of the strut tops on some of the earlier MCS's, and am curious what the symptoms are. Emily has developed a sqeak/chirp when she hits bumps. It's not 100% consistent, but often enough to make me a little concerned.
Any thoughts or ideas?
Thanks,

 

I'll go one better than that...and show off my mechanical ignorance: what is the strut top? I assume it's in the vicinity of the shocks, but that's the extent of my knowledge. And yeah, I'd like to know how you know it's mushrooming as well....

 

Pop the bonnet. On either side of the engine, centered over each front tire, you'll see a body-color tower with a round hole on top surrounded by three nuts and bolts. The body-color towers are the strut towers (the front suspension struts are inside), and the three nuts/bolts are what attaches the upper end of the strut to the tower. Attached to those three bolts is a stamped sheetmetal plate that carries a bearing assembly to which the shock absorber part of the strut attaches.

"Mushrooming" refers to when the top of the strut towers starts bowing upward, due to hard suspension impacts. A noticeable symptom is that the three bolts sticking through the tower start splaying outward rather than remaining straight up and parallel to each other. It's a little harder to tell by eyeballing whether the tops of the towers themselves are actually deformed, but if it's bad you can tell.

I suspect that the upper strut mounts can deform and the bolts start splaying out even without deformation of the towers themselves.

The mushrooming shouldn't cause any strange noises, or really have any other adverse effects as long as one side is not drastically different from the other. The deformed sheetmetal of the towers and/or upper strut mounts doesn't affect the operation of the struts. However, if there have been impacts hard enough to deform the towers and mounts, the bearings in the upper strut mounts could be abused and if they are going bad you may hear some creaking or clicking, especially at low speeds and/or when turning the wheel hard.

 

If your that worried or just want to take precaution like me, than buy a strut tower bar or the m7 strut tower plates. All the bar or the plates are going to do is sandwich the strut tower sheet metal between the strut and the bar or plate, and in doing so making the stut tower a bit stronger. Here is a pic of my engine bay with the m7 stut tower plates so you can see...