Irritating Front NS Knock

[sauntson]

Hi Guys

Well this is getting frustrating. I have a 2016 2.0 Grand Picasso with just under 43k Miles. it as for some time had a knock which sounds like it is coming from the Front NS. I was “reliably” told it would be a strut mount as it is the kerb side. So I took upon myself to change both the mount and bearing. Outcome, I still have the very same knock. so I have tried too carry out further investigations and have come up with this

1, removed the bottom end of the Droplinks and tried pulling, pushing on both ends and no movement found. Purchased a new droplink to quantify and no movement but knock still persists
2, The knock is heard more with only me in the car. When my wife in the Passenger seat it is far less frequent but does it occasionally but at a greater speed. tested at 58MPH running NS wheel over cats eye and heard the knock.
3, When in the car alone. I hear one knock at low speeds but several knocks / rattle at higher speeds when driving over speed bumps or bumps in the road.
4, Have jacked the car up and using a pry bar tried moving all ball joints and steering ends joints and cant see any movement.
5, Have tried wiggling the wheel at 12 & 6 and 3 & 9 and no movement


Is it feasible to be the shocks at such a low milage although 6 years old…… Any help would be greatly appreciated before I put her into a garage and take the financial hit…..

Best Regards

[paulmac1978]

Hi, I had 2015 C4 with issues exactly as you described and it indeed it was the shock absorber itself which had slight play and was causing the knocking sound. The car had done around 60k when the issues started. Removing the spring from the shock is the only way to check.

Genuine replacement shocks from the dealer are quite reasonably priced.

[sauntson]

Hi
Paulmac1978, Thankyou for your reply. If I go for the spring removal. Do you know what I should feel or to do in the checking?

regards

[TZDunnit]

I had a similar thing on my daughters Suzuki Swift, after checking all the usual suspects it turned out it was the nearside steering rack end, this too made "a different knock" with passengers.
Not sure of your set up ut might be worth a look. Bottom ball joints can also knock.

[paulmac1978]

Any play in the shock absorber will be easily noticed once it’s been removed from the spring. There shouldn’t be any movement at all.

[sauntson]

UPDATE, Well The day finally came and I took my car to my friends barn incase the weather turned south and with the forecast 46% chance of rain. First, Removed the scuttle, moved the windscreen motors and loosened the strut mount bolts so they were holding the last 1/3 of thread. Jacked up the car and using axle stands and a rear wheel chock. Removed the front wheels. I started on the passenger side as this was where i thought the main noises were emanating. Removed the Shock assembly as a whole and disassembled. Once I had it apart, I inspected the parts and found the shock had zero rebound resistance. When compressed it, it instantly extended when released (no a slow extended as Id expected) Clearly this would need replacing. Cleaned all parts and replaced the Front Shockc with Bilstein 22-242020 From AutoDoc. The Strut Mount was changed for a Febi 100702 and New bearing Fitted (snr.M259.12). Rebuilt the assembly and installed. Removed the drivers side and after disassembly found the shock had far more rebound resistance. However rebuilt using similar items to the NSF. Once the refurbished shocks assembly had been rebuilt it came time too test. All I can say is she now drives and feels like a new car. The irritating noises have gone and she drives so smoothly. Well worth doing.

[Peter.N.]

I have had this sort of noise just due to the the nut on the top of the shock absorber not being tight.

Peter