Suspension Noise- Dump of thoughts welcome

Post by **dyn blin** » 16 Aug 2017, 20:25

I'm no stranger to P80 suspensions. I've rebuilt/replaced front and rear on 2 850's and a V70, at least twice on one car after "saving" money on cheap parts. I've figured out clunks, clangs, rattles, shimmies squeals and grinds. However, this latest has me stumped.

I have been chasing a single "clank" from the front lowerr left (driver's) side for a month. It sounds when I roll over anything the size of a road dot or larger at speeds of over 10 MPH, and goes away over 45 MPH. It sounds like a metal plate being dropped from a couple inches onto another plate. I've so far :

Inspected spring seats - no issue
Inspected control arms- there is no bearing play
There is no drifitng or vibration at highway speed
There is no play from the wheel when off the ground using the "3 & 9" & "12 & 6" grab and shake
There are no visible cracks in the strut spring
Sway bar bushings appear intact (hard to determine integrity as they are vulcanized)
Upper engine mount is good.
I even replaced the anti-rattle springs on the left front caliper.

This weekend I'll be re- checking the left side lower engine mount (a visual last week didn't see any obvious cracking or leaking)

Yesterday I replaced the sway bar links with the Meyle HD (previous were Volvo-branded, installed during a front end axle & suspension refresh 40k ago). This has made the sound lessen in frequency and severity, so I may be on the right track...

Suggestions on where to relook, or what I may have overlooked are appreciated!

(Edit- outer tie-rods replaced in April, inner done 40k ago with the suspension refresh - no sound trying to manipulate them from under the car when tensioned and resting on the suspension)

Post by **scot850** » 16 Aug 2017, 23:13

I have spent hours trying to find a groan and knock from my front suspension. Everything has been replaced in the last 10-12kkm.
I am currently on the 3rd set of end-links, and the dealer has just fitted the 4th on the RHS. They have had the car for a week and used many things including a 'magic ear' while driving he car but could not pin-point it. Finally, the foreman had the apprentice remove one end-link and the problem stopped. The conclusion is the sway-bar bush is bad. I had a used one fitted about 3000km ago and about 18 months ago. He says the bush looks good but it must be bad on the RHS. From my perspective I am wary that this is the solution as I had then remove the IPD HD front anti-sway bar as it was groaning too. 2 new sets of bushes from different manufacturers made no different. Hence the 'wait and see' from me. I have given them the ok to replace the sway-bar with a new OE one as I am so fed up with it.

Coincidentally I just got the IPD sway-bar returned from powder coating today and was tempted to re-install that again, but it can stay off for now to prove a point.

I'll let you know how it goes.

The apprentice did swap the Meyle HD end-link on the RHS and said it did lessen the issue but did not fix it. So far the RHS has had an OE Volvo, IPD HD and Meyle HD and now back to OE Volvo.

They also fitted my 2 new lower control arms.

On the other project V70, I was getting a knock on the LHS front and it turned out being the end-link. It looked ok until removed and it was bad.

Neil.

Post by **dyn blin** » 16 Aug 2017, 23:23

Thanks Neil,

Misery loves company. Maybe we should combine efforts and go for a record length list of "what it's not"!

Klausc · Post by **Klausc** » 17 Aug 2017, 11:46

Dyn, does the noise go away if you put just a small amount of pressure on the brakes? The inner pads have 3 prongs. I had one of them break off. The noise went away under braking. I used a rubber mallet and pounded on everything I could find, when I hit the caliper - there was the clank!

Post by **theWIFES_S70** » 17 Aug 2017, 19:03

Klausc wrote: ↑17 Aug 2017, 11:46 Dyn, does the noise go away if you put just a small amount of pressure on the brakes? The inner pads have 3 prongs. I had one of them break off. The noise went away under braking. I used a rubber mallet and pounded on everything I could find, when I hit the caliper - there was the clank!

Klausc, what was this noise like? a clank? I've been trying to track down a control arm bushing-LIKE "KREEAK" sound that I cannot for the life of me identify. (Lemforder arms, steering is great, wheel doesn't move at all.) I guess I'll give all the front brake parts a look. I should regrease myslide pins anyhow.

Post by **scot850** » 17 Aug 2017, 19:10

That may well be the CREAK/Groan I was getting from my 'R' front suspension. Hopefully I might get the car back tomorrow if the new anti-sway bar comes in and can get fitted. Still not 100% sure this is all done and dusted, but have to at least try to be optimistic and hope the noisy sway bar bush is the issue. Apparently the problem sourcing the issue was that the noise seemed to travel through the whole suspension giving the impression it was in every part.

I'll update when/if I get the car back.

Neil.

Post by **theWIFES_S70** » 17 Aug 2017, 19:47

scot850 wrote: ↑17 Aug 2017, 19:10 That may well be the CREAK/Groan I was getting from my 'R' front suspension. Hopefully I might get the car back tomorrow if the new anti-sway bar comes in and can get fitted. Still not 100% sure this is all done and dusted, but have to at least try to be optimistic and hope the noisy sway bar bush is the issue.

If my KREEAK is coming from the from anti-sway bar, my wife is going to have to get used to the sound...

I wish you could upload audio or videos of your sounds, Neil. Good luck!

Post by **dyn blin** » 17 Aug 2017, 23:37

Klausc wrote: ↑17 Aug 2017, 11:46 Dyn, does the noise go away if you put just a small amount of pressure on the brakes?...

Great idea. I'm about to take her on an 1800 mile excursion, and will get to experiment if the rubber mallet test doesn't reveal it.

Thanks for the idea.

Post by **scot850** » 22 Aug 2017, 15:26

Well promised an update when I got the car back. Still not convinced it is 100% fixed but nearer 95%. Still the occasional noise but some of that is the muffler in the rear. Main thing is it is drive-able now without sounding like the front suspension is about to collapse! Cost, $1400 CDN for the new anti-sway bar (OE), and the fitting of the 2 front lower control arms and a new end-link (these parts I supplied and were about another $500 CDN), so total is about $1900. For all that money what have I achieved?

There is the occasional noise but I can live with that so I am ok. But what was the problem? Unfortunately they did not leave the old anti-sway bar for me to dissect to understand what had happened to the bush on the RHS. I have got the end-link (Meyle HD) and the 2 front lower control arms (unknown aftermarket) back so I will check them over also as I think it was a combination of poor parts and not a simple issue.

Neil

Post by **theWIFES_S70** » 22 Aug 2017, 23:02

Neil, how does that new front sway bar make the car feel? Is it a big difference? I was watching one of rspi's video's (the one where he gets that front sway bar put in) and when he disconnected his sway end links the bar, it just falls down. The old one had nothing vulcanized at all! Was your sway bar like that?

It's the only weak component in my suspension and I'm thinking that's where my noise is coming from. That and possibly the steering rack...