Rear coilover clunking

Okay, so I've been getting this annoying clunking sound from the rear of my car, even on small cracks on the road, for the past several weeks now. Sounds similar to turbo_911's problem a couple years back. Last week I replaced my rear sway bar bushings but that didn't eliminate the noise whatsoever. Earlier, I captured a video of this..

Clunking

When I try to twist the spring around, it's tight but it seems as if there's a slight gap between part of the very-bottom coil and the spring perch that's causing the sound.

Do I compress the spring more (move the 2 perches up a bit) or should I buy those Tein Silencer rubbers and place it between the bottom of the spring and the perches? I'm thinking the latter.

If there's play in the spring then adjust it so there's none. That can cause clanking.

The spring should not have movement up/down, it should be actually compressed 5mm from its free length. If they were never re-compressed after installed when new what could've happened is the spring is now broken in/sagged a bit.

Personally i'd do both.
#1 Make sure the spring is compressed 5mm from its current length now
#2 Add the rubber silencers

Thanks guys.

Well, I just came back from a local tuner shop and they didn't carry the Tein silencer rubbers but the guy gave me this (don't know what it's called), which he said is essentially the same.

001Stunna said:

The spring should not have movement up/down, it should be actually compressed 5mm from its free length. If they were never re-compressed after installed when new what could've happened is the spring is now broken in/sagged a bit.

Personally i'd do both.
#1 Make sure the spring is compressed 5mm from its current length now
#2 Add the rubber silencers

Click to expand...

The pre-load was never touched and stayed the same from when it came BNIB. About the spring being broken in, that seems to be a good point.

So compressing it another 5mm isn't going to completely throw off the preload and prematurely decrease the life of the shocks, would it? I had an alignment done last week, would I need one after doing this?

What they gave you would serve the same purpose...it's basically there just to soften the metal/metal contact.

As for the preload; from all the FF sets i've seen and helped out on I've found none of them to be to FFs specs for preload when out of the box brand new. Some have been tightened too much and some not enough. I've always just loosened the spring perches fully; measured the spring; compressed it 5mm from its free length; and then gone through with installing them on the car after lubing everything with grease.

Would you compressing the spring 5mm make a difference? Yes it will make possibly a small minuscule difference.

Reason being as...right now the spring does not start compressing until that small amount of movement compresses into the shock body first(this is assuming the car in the air and the damper under no compression force at all)
Once you create the correct amount of preload, the spring will begin its compression at once with no free play in it.

I would assume the end result will be a very very slightly higher ride height after you preload the spring. It's hard to say if you'll need an alignment or not though but if you've got the whole lifetime alignment deal then Yes get it.

One thing to keep in mind though is that when you drive your car the spring is loaded at all times no matter what you have set the preload to as the weight of the car is on it. Hence why I would think doing both #1 adding the rubber silencer, and #2 making sure the spring preload when free is correct...should hopefully fix things if it is coming from the coilover itself

truWarier02 said:

Thanks guys.

Well, I just came back from a local tuner shop and they didn't carry the Tein silencer rubbers but the guy gave me this (don't know what it's called), which he said is essentially the same.

The pre-load was never touched and stayed the same from when it came BNIB. About the spring being broken in, that seems to be a good point.

So compressing it another 5mm isn't going to completely throw off the preload and prematurely decrease the life of the shocks, would it? I had an alignment done last week, would I need one after doing this?

Click to expand...

Brought it to my go-to mechanic today and he took a test drive. He said that it would clunk on just about every little bump. Initially, he thought it was the spare-tire flap flopping up and down because my mini subwoofer is weighing it down in one corner and propping up the other corners. Well, that made me feel stupid! But anyway, afterwards I got some towels and wrapped around the whole edge of the flap. Went for a drive and surprisingly, that didn't get rid of the main clunk.

Next, he put the car on the lift and used a pry bar on pretty much every arm in the rear, everything seemed nice and tight with no play. Then he put a towel under the rear deck panel. It seemed to have dampened the noise and the clunk occurred less frequently.

Could the rear deck or something inside be flopping around due to daily driving with coilovers? Maybe there are bolts under there that may have gotten loose. What I noticed for a period of time last year was that I would hear a creaking sound, like chassis flex or something. Nowadays, the creaking (probably something slowly getting loose) is completely gone and I guess it has now progressed to clunking.

He also kept reassuring me that it's not my suspension. He jumped up and down inside the trunk and it was actually completely quiet. Still sucks that I can't pinpoint the culprit, but it's good to know that it's not from my coilovers.

Brought it in to a local tuner shop today. Went for a testdrive with the owner and he immediately noticed the stupid clunking from the rear driver deck area. So he took that coilover out to inspect it and everything looked normal; but when he pushed the damper down, it only went halfway and beyond that, he would have to exert more force to push it all the way down. I'm guessing most of the oil had somehow disappeared, although I never noticed any fluid leaking from my coilovers.

So I went to the F2 headquarters about 30 minutes away to pick up a replacement damper for $75 + tax (not too bad). Afterwards, went back to the tuner shop to have it replaced.

The annoying, obnoxious clunking is finally GONE!!!!!!! It's extremely quiet now.

On the down side, I have to get another alignment now, which I had done just 2 weeks ago

are f2's oil or gas filled? one on the front and one on the rear clunk on mine and i'm pretty sure its the shocks, but i wasn't sure because nothing ever leaked from them...that i could see anyway haha. when one of my ksports blew, there was oil everywhere haha...and i should've gotten them again. they lasted 4 years, while one of the f2's started making noise two days after i put them in.

I think it's oil filled. But yeah, I never saw any fluid leaking from the affected coilover, that's why I figured the coilover itself was fine. It's weird because if I pushed the rear down, I didn't hear any noise but going over the slightest imperfection on the road would result in a clunk. I've had mine for almost 2 years now and it's my daily driver. Aside from this isolated clunking issue though, these type 1's have been a nice ride, not too harsh and not too "boaty."

This was turbo_911's car. Does your clunking sound like this? I don't think he ever found a solution for it though.