Evening everyone,

Apologies in advance if this is not the appropriate section for this, if so just let me know and I'll move/delete this.

Just finished up a replacement of the struts/shocks on the car, ended up going with Koni FSD with stock springs based on some positive reviews I had read online. Unfortunately, I drove the car for the first time post-install today and I am getting clunking from the rear over bumps. I am confident that the two top mount bolts and bottom bolt are torqued to spec, but I admit fully I was unable to measure torque on the single strut nut at the top. Compound that with the reality that I think a rear caliper may be dragging and I am definitely growing weary of fighting the car. Had to replace the entire oil filter housing assembly for the last oil change, it never seems to end!

I am planning to pull the rear suspension back out of the car tomorrow to get photos to help, but my questions are as follows:

• Does anyone have an install DIY for the Koni FSD suspension? I found some old threads but were plagued with dead links. The shocks came with very little hardware, but they did include 2 nylon washers maybe 1.5" in OD. I tried to reassemble the struts using only the hardware that came off the old units (nylon washers are still in the box unused), but clearly that was not successful. I thought I read somewhere that these are required for install with Koni yellows, but I am struggling to understand their purpose?
• Top nut torque - I believe this is supposed to be 22 ft-lbs, but I doubt it is under-torqued as is. I had significant compression of the rear shock mount bushings (which I replaced) such that they 'ballooned' out in a way vaguely similar to that which I've seen on old BMWs
• Top rear strut assembly washer (immediately below the strut nut) - is it supposed to be angled? The units I removed from BMW rears were always flat/flush with the bushing, but both sides looked like this so I assumed it was intentional
• Are there any tricks I should be looking for here otherwise? Anything specific about FSDs that would have prevented me from simply installing the rear with existing OE hardware?

Appreciate any advice, feeling a little bit at wits end after replacing it all only to find it sounds 100x worse than before ... Thankfully I was able to mostly remedy the mushrooming at the front. As an aside, I did not touch the rear swaybar/endlinks/control arms, so I am confident I effectively created the noise by replacing the strut

Cheers!

 

Are you sure it's your shock or struts causing this clunk ?
perhaps it isn't and the stiffer suspension has now just made the prior problem louder.
Have you checked you rear sway bar bushings ? Befor you attempt to redo it, inspect anything suspension related back there , you might be over looking something .

 

First check that you have the top shock nut completely tight. It's a common thing, I thought mine was tight and turned out 1 was not all the way. Next would replace the sway bar end links. Meyle HD links I was told are the best OEM type. I have not put mine on yet but when I checked the ones on the car it felt like they had good resistance when moved in a circular motion, until I got the new ones and realized I could hardly move them at all by hand.

 

That plastic washer is some kind of bump stop that Knoi uses to keep the shock from going all the way down and blowing out the seals. Not sure if it really applies to all cars but I can't remember getting a set of Koni's that did not have them. Picture of the nut / split washer would help anyone to tell if something is wrong with that.

 

Thanks for the feedback! I was pretty sure it was the shock/strut - as it turned out my suspicion was correct. I checked the rear swaybar bushings and didn't find any play, I removed the struts and retorqued the top nut. I thought I had achieved the ~22 ft lbs required but it turns out the nut had gotten caught on some threads that were slightly gummy. Once I pushed past this resistance I was able to tighten until it truly bottomed out. For those comparing to the OEM struts, based on my memory there ended up being far more threads exposed above the top of the nut on the Koni FSDs than on the OEM hardware. This lead to some of my confusion/concern initially, as I thought I was overdoing the nut.

You're 100% right, it was the top strut nut! Thanks for the help. Ended up putting Meyle HD endlinks up front, will be doing the rear soon with the same hardware. Car is in for an alignment now, it rides much better than the blown OEM stuff that I yanked out. Also nice to have strut towers that are somewhat flat again.

Makes sense! I ended up leaving it out, as I came to a similar conclusion. I found some Porsche/BMW guys who similarly omitted it digging on other forums. Hopefully that doesn't come back to bite me long term haha.

Thanks everyone for the help! Was definitely at wits end a bit, but it's back together and clunk-free now!

For future reference in case anyone finds this thread for Koni FSD install:

The Koni FSDs (sourced from WMM) were able to be installed with 100% OEM hardware. I do not believe I used any of the Koni supplied hardware. The front strut nut, for example, was too large to fit a socket onto when installed in the car (which lead me to reuse OEM). Neither the rears nor fronts required any modification to the OEM hardware, but care has to be taken to actually get the strut nut to the point of bottoming out especially in the rear. The rear strut mount bushings do 'balloon' under this torque with the angled washers (which are factory). The ride is also dramatically improved with this setup, will see how long it stays this way!

Hopefully this proves helpful to future FSD installers, I had much more difficulty than usual because I normally base my expectations on the appearance of the OEM stuff I'm pulling out. In my case the OEM hardware (at only 77k) was nothing short of ruined.

 

I just replaced all my old struts and shocks with the Konis too ( check my post about it) and had no issue. I replaced all the mounts with new ones and made sure to torque EVERY single nut to the exact spec. Had no issue at all and I'm very happy with the performance of these items after a full month or so. Super easy job too!

 

I just replaced both rear shocks with Koni Special Active. Took the car for a test drive and had some major clunking from the driver's side, but the passenger side was nice and quiet. Reading over a bunch of other posts, I decided to replace the end links on both sides to see if that would help with the clunking noise. The original end links were not too bad, but the new ones were stiffer at the upper connection. Took the car for another test drive and the clunking was still present. Searched the forum some more and found this post which talks about the small washer having a chamfered inner edge. I honestly could not remember seeing that nor if the new shock had the chamfer on the rod. Mind you that I made sure to torque everything to spec since most people blame incorrect tightening as the culprit for the clunking. Took the shock off the car and disassembled it to find I had the washer upside down. After flipping the washer and putting the shock back together with the correct torque specs, I took the car for a test drive and everything was nice and quiet. Lesson learned: make sure the little washer is not upside down.

 

Koni FSDs are night and day to any stock setup. Highly recommended. This should have ben OEM from the beginning!!!!

 

I was wondering about that white plastic washer as well, I've got the top nut cranked as much as possible yet there's still a tiny bit of wiggle in the strut mount bearing. I thought maybe I should've put the washer between the strut mount and the coil spring seat, but maybe not. I'm going to attempt tightening more using an O2 sensor socket (which is 7/8 and close to 22 mm), but worried about mangling something if I'm too ham-fisted. I took some photos of the "instructions" that came with the Koni Special Active shocks, in case they're helpful to anyone on here. (or if someone can decipher some of them)

 

I don't recall which instructions came with what, but I think this is for the front Koni S.A. struts

I think these were for the Koni S.A. rear shocks

Uhhh.... something something torque numbers?

 

Just curious what you guys used to torque the top nut on the rear konis. Since you have to use a 5mm allen key to hold the shaft how did you get a torque wrench on the nut. I just used a gear wrench on it until it bottomed out and was nice and tight. I also put the white plastic washer all the way at the bottom of the shaft under the factory foam bump stop.

 

To torque the top of the struts, what you really want is the Schwaben Strut Nut Socket (or equivalent): https://www.google.com/search?q=Schw...rut+Nut+Socket

The allen key fits through the "window" on the side of the Schwaben tool. (You will likely also need a "cheater"/extension for the allen wrench.)

 

I used a rather nifty trick because I dont have the special tools. I used some thick rubber and some pliers to lock the shaft. Then I was able to tighten the top nut. I used an impact wrench btw. Please note that I wouldnt use an impact without this method as the shaft would be just spinning around!

I cant remember exactly, but I dont think I needed to use this trick on the rear struts...

 

I just wound up tightening as tight as I could get with my long gearwrench box wrench and allen key. It's only like 22 ftlbs so I'm sure I got it tight enough.