[Johnkwick]

Hi everyone,

I just replaced my shocks 4 months ago (replaced my OEM-non VDC with Sachs) and I replaced almost anything related to suspension (long tie rod, control arm, thrust arm, sway bar link, sway bar bushings) at the same time to fully refresh because my car made clunky sounds when going over uneven roads.

Fast forward to present time, I noticed a squeaky sound (it's been 2 months) whenever I ride over a road bump (squeaky like moving/pressed rubber) and I can reproduce the sound when I pushing down the front side of the car for multiple times. Sometimes I had rattling/clunking sound at low speed which is common symptom from worn out bushing/arms but that shouldn't be the case because I already replaced all front arms.

So I brought my car to a reputable indy shop today, and after they did the inspection they said that my front shocks are basically dead. They also stated that there are multiple cases which involves Sachs where their shocks prematurely worn out or even dead so they decided to choose Bilstein B4 as OEM replacement since then.

They asked me how the ride feels and since the road around my commuting area are in pretty bad shape like potholes everywhere, bumpy road, and poorly-created road bump (tall but narrow like you're driving over a triangle shaped bump), what I really feel was it's a jarring experience.

They decided to remove the shocks and springs and see if there's resistance on compress, to my surprise the front shocks are quite easy to compress however it's still coming back to its initial position not long after (is this normal or should it be pretty hard to compress?). As for the rear shocks, I can tell that these things require more force to compress.


Initially I just wanted to replace my front shocks but they didn't recommend to mix shocks' brand in a car. So I replaced all shocks with Bilstein B4 for $550 (parts and labor included) which should be super reasonable but it's not because I paid $1100 in 4 months span for 2 complete set of shocks, shocking!

No more squeaking sound, no more clunking or rattling sound, smoother ride but not that smooth considering the condition of the road.

Correct me if I'm wrong, to my knowledge, if the compression resistance on shock is completely gone then it wouldn't able to support the weight of the car and also negate the shock's rebound. Thus, my car had been riding on spring for months. Does my assumption make any sense?

[Hoa]

If your strut compresses and does not come back by itself or rise back to its original height, it is bad. It should be easy to compress. I don’t think your sachs replacement shocks are bad. Squeaking sound usually is a rubber that makes that noise. Perhaps when you torque it down, it settled after some driving and is a little loose so it squeaks and just require to torque it down once more. If you hear a clunk, it’s a sign of a bad top hat or blown strut. When compression is gone, the springs will still be able to hold up the vehicle.

[StradaRedlands]

Originally Posted by Johnkwick

Hi everyone,

I just replaced my shocks 4 months ago (replaced my OEM-non VDC with Sachs) and I replaced almost anything related to suspension (long tie rod, control arm, thrust arm, sway bar link, sway bar bushings) at the same time to fully refresh because my car made clunky sounds when going over uneven roads.

Fast forward to present time, I noticed a squeaky sound (it's been 2 months) whenever I ride over a road bump (squeaky like moving/pressed rubber) and I can reproduce the sound when I pushing down the front side of the car for multiple times. Sometimes I had rattling/clunking sound at low speed which is common symptom from worn out bushing/arms but that shouldn't be the case because I already replaced all front arms.

So I brought my car to a reputable indy shop today, and after they did the inspection they said that my front shocks are basically dead. They also stated that there are multiple cases which involves Sachs where their shocks prematurely worn out or even dead so they decided to choose Bilstein B4 as OEM replacement since then.

They asked me how the ride feels and since the road around my commuting area are in pretty bad shape like potholes everywhere, bumpy road, and poorly-created road bump (tall but narrow like you're driving over a triangle shaped bump), what I really feel was it's a jarring experience.

They decided to remove the shocks and springs and see if there's resistance on compress, to my surprise the front shocks are quite easy to compress however it's still coming back to its initial position not long after (is this normal or should it be pretty hard to compress?). As for the rear shocks, I can tell that these things require more force to compress.


Initially I just wanted to replace my front shocks but they didn't recommend to mix shocks' brand in a car. So I replaced all shocks with Bilstein B4 for $550 (parts and labor included) which should be super reasonable but it's not because I paid $1100 in 4 months span for 2 complete set of shocks, shocking!

No more squeaking sound, no more clunking or rattling sound, smoother ride but not that smooth considering the condition of the road.

Correct me if I'm wrong, to my knowledge, if the compression resistance on shock is completely gone then it wouldn't able to support the weight of the car and also negate the shock's rebound. Thus, my car had been riding on spring for months. Does my assumption make any sense?

Bilstein has a limited lifetime warranty, just get them replaced.
https://offroad.bilstein.com/en-us/warranty/

[Johnkwick]

Originally Posted by Hoa

If your strut compresses and does not come back by itself or rise back to its original height, it is bad. It should be easy to compress. I don’t think your sachs replacement shocks are bad. Squeaking sound usually is a rubber that makes that noise. Perhaps when you torque it down, it settled after some driving and is a little loose so it squeaks and just require to torque it down once more. If you hear a clunk, it’s a sign of a bad top hat or blown strut. When compression is gone, the springs will still be able to hold up the vehicle.

I was thinking the same thing tho. But then the noises were completely gone, neither squeak nor clunk were heard when I drive so yeah I think I'll move on.

Unfortunately, majority of the OE replacements are distributed through 3rd party or independent importer which means warranty for those things are simply non existent. So when thing like this happens, filing warranty claim is to merely wasting my time.

[HighlandPete]

Originally Posted by Johnkwick

Correct me if I'm wrong, to my knowledge, if the compression resistance on shock is completely gone then it wouldn't able to support the weight of the car and also negate the shock's rebound. Thus, my car had been riding on spring for months. Does my assumption make any sense?

Shocks (dampers) don't carry the weight of the vehicle, springs do that job.

Remember that the speed of compression of a damper, is part of how it works. Simply compressing it by hand isn't the true measure of a damper's efficiency.

Some of your description does indicate rubber components may be involved. Was it at least in part a bad initial install? Were suspension parts torqued in the loaded position?

[Johnkwick]

Originally Posted by HighlandPete

Shocks (dampers) don't carry the weight of the vehicle, springs do that job.

Remember that the speed of compression of a damper, is part of how it works. Simply compressing it by hand isn't the true measure of a damper's efficiency.

Some of your description does indicate rubber components may be involved. Was it at least in part a bad initial install? Were suspension parts torqued in the loaded position?

Hi Pete, pardon my ignorance, but if the damper is relatively easy to be compressed by hand, does it mean that in the moment of vertical sway, the car will bounce according to the spring rate because the damper simply could not absorb the movement? (I refer this as riding on spring)

I wouldn't rule out the possibility of bad installation because every indy shop I ever visited don't have basic knowledge like proper torque spec for bolts, pre-load condition on arms, etc etc.

If I recall correctly, tires & wheels were off and they lifted the lower control arms to ensure that the bolt could be inserted and torqued in droop position.

[HighlandPete]

Originally Posted by Johnkwick

Hi Pete, pardon my ignorance, but if the damper is relatively easy to be compressed by hand, does it mean that in the moment of vertical sway, the car will bounce according to the spring rate because the damper simply could not absorb the movement? (I refer this as riding on spring)

I wouldn't rule out the possibility of bad installation because every indy shop I ever visited don't have basic knowledge like proper torque spec for bolts, pre-load condition on arms, etc etc.

If I recall correctly, tires & wheels were off and they lifted the lower control arms to ensure that the bolt could be inserted and torqued in droop position.

If the dampers are really shot, then yes, there will be uncontrolled bounce and float.

A better test (without a damper test rig) is trying for faster up and down movements of the damper rod, when using bench conditions. I've done this in the past, and that soft initial stroke becomes resistant to movement, as we would expect as speed increases.

Tightening and torqueing wishbones (upper and lower) and control arms, must be tightened at the normal ride height, not hanging. Rubber bushes that do not spin in the housings, are designed to be at the correct ride height as the 'seated' position when tightened.

[KrWarmRobot]

There are many problems like this in Korea, too.

BMW owner's club in Korea is noisy over this issue.

The noise occurred even though all the parts involved were replaced.
(Control Arm(U/L)(Lemforder), Tie Rod Assy(Lemforder), Stabilizer Bar(Genuine) & Link(Lemforder), Shock Mount(Lemforder), Pad(U/L)(Genuine) Etc....)

The technician said there were no more parts to replace.

Finally, the noise disappeared only after replacing the SACHS Shock with a genuine one.

We invested a lot of time and money because of the noise that occurred just a week after installing SACHS Shocks.

Because I never dreamed that SACHS Shocks were the cause of the noise.

Not only me, but other car owners in Korea are experiencing the problem, so we are trying to jointly respond.

We have contacted ZF and SACHS Company about this problem.

If you are experiencing the same problem or feeling stressed, please reply.