i had coil overs on my 996 and didn't make the noise, i'm also getting kind of springy bouncy ride when i hit bumps..

 

well... maybe I got defecting one.

 

lol, no i'm sure you didn't, its a common thing, but while its common, also seems in some posts that the culprit turned out to be the install in some of the instances and in other instances its just the nature of the shocks.

 

It's the top bearing plates (which are removed when damptronics / pss9/10 are installed). I installed some needle bearings between two plates, no more clunking.

 

The spring pop saga continues.

After about 3 years I had my damptronics removed due to a clunking noise inside one of the front struts. I sent the fronts to Bilstein and they found them low in grease/oil so replaced it with their new higher temperature oil which they said would solve the problem. After debating with myself for six months I finally decided to re-install them recently. BTW, when I sent my struts for repair, they still had the top hat assembly since they were removed in tact and replaced with in-tact factory struts (no parts had to be swapped over).
Since re-installing them, I'm getting spring pop when turning, especially at low speed when you can hear it better. I never had any spring pop issues during the first 3 years on the car. I've tried spraying silicone spray on the spring perches top and bottom etc but to no avail. Today I jacked up the front end again and put jack stands under the wheel carriers to load the struts and see what is going on. I found that the driver's side top strut bearing (right under the hat) doesn't turn with the spring, causing the spring to have to squirm on the plastic shims at top and bottom perches. This causes the spring pop. The other strut top bearing turns fine, so there is no squirming or popping noise there. In photo below it is the silver spring cap on driver's side that isn't turning with the spring.
Anyone have any idea what might be causing this? I suppose I'll need to remove the strut and remove the top hat to take a look inside. I'm hoping I can do this without impacting the recent alignment settings, which should be possible given I'm not changing any eccentric settings or height setting.

UPDATE: I took my strut apart. It appears it was simply due to the top hex nut being too tight so that the bearing underneath the upper strut mount couldn't turn. I re-greased the bearing while apart, then reassembled with less torque on the hex nut so that the spring cap can turn on the bearing. I wonder how many other people who had this problem could have resolved it with this fix.

I haven't road-tested yet, but I could tell that while loaded on jackstands the springs are now able to turn on the bearing rather than twisting on the plastic shims.

UPDATE: May 2: After a few hundred miles I'm still problem free. The struts are totally quiet, and the car handles amazingly well.

 

Pretty incredible when you think of it.

At least three or four years and this problem lives on.....so many people putting up with it.

 

All do respect Kenin...........I can't see where loosening the nut in the trunk would help free up the coil-over spring below. I do not have the answer but it seems a good guess the issue is still the binding friction contact of the spring to the large offset spacer. No Teflon washer there just metal on metal.

 

My post, like the others in this thread, was in reference to the front struts, not the rears. The front coil-over springs obviously need to turn when turning the front wheels. If the top bearing can't turn, the springs will then have to slip against their teflon washers, which causes the "sproing" sound. My top bearing was torqued so tight on one side that it couldn't turn with the spring. I've been driving my car a lot for the past few weeks and it is not making any strut noises anymore, including backing slowly and turning out of my garage.

 

Interesting...
Ken, when you "loosened" the hex bolt at the top of the strut, did you turn clockwise or counterclockwise? if you turned it counterclockwise, it seems that you would have actually tightened it.

 

Yep....front struts is all I have always talkesd about also.

Sorry.......gota pull out some pics and try to understand which nut we are talking about that would be binding up a "top bearing".
With no load on the front suspension, that whole assembly is loose and free to turn on both sides....in my case anyway.
Thanks

 

There is a bearing (which should have been removed from the factory strut assembly and moved, along with the top mount, to the Bilstein) that is right under the top strut mount (see second photo below). It is between the silver collar above the spring and the strut mount. It allows the spring to rotate relative to the strut mount. Even with no load from the spring below, I was not able to twist the silver collar by hand until I backed off the top hex nut, shown in 3rd photo below.


I don't know why you think this, as it is a standard thread on top, so screwing the nut counterclockwise did indeed loosen it and allow the "pinched" bearing to move.

 

I recall a similar situation with another set of coilovers. When ignorant mechanics install your set, this can happen. I recall the torque setting for that bolt is very low - like light hand tightening. That's why it's an aircraft nut - it won't loosen even if it's not that tight. A typical grease monkey will try to tighten it with an impact driver!

 

Funny thing is, they were fine until I sent them to Bilstein to service, and it appears they were the ones that over-torqued one of the two struts. I agree it was likely done with an impact driver. Do you happen to know what the correct torque is? I just tightened enough to allow the bearing to move without being too loose. I'm tempted to add a lock nut just to be sure it doesn't back off.

 

oh, for some reason i thought you were using a hex wrench to tighten/loosen the nut, not actually the nut itself. I can't even access the nut on the strut

 

Not sure on the 911 exactly, but it should be accessible. You can't just turn the nut, you need to hold the strut rod with a hex wrench. Bilstein should provide a torque setting for the bolt. From all the pics, this should already be an aircraft nut.