Technical Creaking noise over speedbumps

[Sylvester22]

Hi all, a creaking noise coming from the front suspension since purchase in November, the previous owner said something about small issue, like loose heatshield.
I've done the oil change few days ago, an experience for sure, and fixed the loose heatshield too, but that wasn't the cause at all.

It's only the front section, and if I go very slowly over bumps, then I can't hear it.
The noise is like thin metal layers scraping.
It's a petrol car, but the pre-owner had changed the springs all-around to diesel ones, he said due the front was too low.

The tower struts on top, look good and solid, someone has mentioned to put WD40 on some bushed by the wheels? What can I check? Cheers

 

[the green vanper]

Hello,

WD-40 is not a lubricant. I have no idea how it affects rubber in longer period of time.

If you hear it only driving over speedbumps, most likely it's the suspension. Or the engine suspension

 

[Sylvester22]

Hello,

WD-40 is not a lubricant. I have no idea how it affects rubber in longer period of time.

If you hear it only driving over speedbumps, most likely it's the suspension. Or the engine suspension

Hi GV, I've had a look around and all seems fine, no leaks or holes on rubber covers. When I put weight in the side fenders, there's no creaking.
What shall I check? Cheers

 

[bsks]

Does it do it only in cold weather? I would bet on anti-roll bar bushes, but if it goes away after the engine is warmed up wouldn't worry too much about it.

 

[Sylvester22]

Does it do it only in cold weather? I would bet on anti-roll bar bushes, but if it goes away after the engine is warmed up wouldn't worry too much about it.

It does it in every temperature, and with engine cold or hot.
What I've found a video showing this, it's on a different car not Fiat, saying this rubber seal may need re-greasing if creaking sounds appears over bumps.
Any idea? Cheers

 

[bsks]

If you have the tools (and time) you can jack the front of the car up, remove front wheels, disconnect both anti-roll bar links (from the top nuts, easier access) and move the bar up and down to see if that is the source of the creaking. As for greasing, there are different opinions. Some say yes, some say don't. Rubber friendly grease must be used, and the bushing brackets must be disassembled with the ARB removed from the vehicle, and this is not a very nice job since the bar is mounted on top of the front subframe. That's why if the car drives fine and there are no weird clunks or knocks, i would leave it as it is.

Edit - other sources of creaking might also be the shock absorbers, control arm front bushes, ball joints.

 

[the green vanper]

Rubber friendly grease must be used

Silicone grease should do the job.

 

[bsks]

I've also read that plumber's teflon tape can be rolled between the bush and bar.

 

[Sylvester22]

As for greasing, there are different opinions. Some say yes, some say don't. Rubber friendly grease must be used

That does seem a tad out of my mechanical knowledge unfortunately, in the video the guy just sprayed silicone spray around the area without disassamble.

I've tried to recreate the noise by rocking front fender area and the whole chassis from the a-pillar, but no creak.
When I hit a pothole, I can hear some cracking all around, but not as strong as speedbumps cause. Cheers

Silicone grease should do the job.

I've got rubber friendly WD40, cheers.

I've also read that plumber's teflon tape can be rolled between the bush and bar.

That's interesting, I'll look into that, cheers.

 

[the green vanper]

I've got rubber friendly WD40, cheers.

I wouldn't be so sure...

 

[Sylvester22]

I wouldn't be so sure...

I've got this one, I hope it's good as it wasn't cheap.

 

[the green vanper]

Yes, it's the silicone spray Should be OK.

Usually when people say 'WD-40' they mean their first product, from which the brand took the name. Which the idea I don't hmm... understand The product, not the name

 

[Sylvester22]

I would bet on anti-roll bar bushes, but if it goes away after the engine is warmed up wouldn't worry too much about it.

Hi bsks, I drove around a bit today, over an hour, and upon testing the speedbumps-creaking, that noise indeed has been much quiter with warm engine. It doesn't fade away completely, but 80% less, so big difference.
I assume the silicone spray is just a temporary solution. I've read when you'd similar issue, how long could it last before those bushes need replacing? Cheers

 

[bsks]

I'm not sure

 

[The Panda Nut]

May be a day, maybe amonth or more. Short term fix ia strong solution of washing up liquid and water, but that doesnt last long

 

[Sylvester22]

May be a day, maybe amonth or more. Short term fix ia strong solution of washing up liquid and water, but that doesnt last long

I assume if it starts knocking at every bumps, now only at bigger speedbumps, that's when the issue need proper repair? Cheers

 

[The Panda Nut]

I assume if it starts knocking at every bumps, now only at bigger speedbumps, that's when the issue need proper repair? Cheers

It may quieten down. Sometimes it is just caused by dry bushes. Treat them two or three times a few days apart and you may be lucky and cure it. Replacement is required if they are worn and things are moving about when they need to be held secure. You just need to keep an eye on it.

 

[blastafuri]

I found that plastic repair sprays, usually meant for trimmings, bumpers, etc... do a nice temporary job on rubber parts. I also use it on squeaking belts without any issues. I

 

[Sylvester22]

I found that plastic repair sprays, usually meant for trimmings, bumpers, etc... do a nice temporary job on rubber parts. I also use it on squeaking belts without any issues. I

Careful with those regular contact sprays on rubber parts, as they'll deteriorate that material, even regular WD40 isn't good, but the WD40 SILICONE spray is specially made to be rubber friendly.