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-   -   Knocking front end on rough roads. (https://forum.a8parts.co.uk/showthread.php?t=16690)

Prefferle 29th May 2022 02:22 PM

Knocking front end on rough roads.
 
Hi folks, can anyone advise how to check the front driveshafts / CV joints for wear tolerances? I’ve had a mysterious knock coming from the front of the car and it’s only getting worse over time. I’ve replaced virtually everything and thinking it must be axles or ??
I’ve got nothing left to replace except the steering rack or front axles however, when I replaced all the inner and outer tie rods the rack shaft and mounting bolts are tight with no play, I even tightened the rack tolerance adjustment which tightened up the steering slightly but there was no steering play anyway…
All front suspension arms, tie rods, steering rack bolts checked, stabiliser bar with drop links replaced, both front air struts - all replaced with NEW parts in an attempt to get rid of this illusive knock. It’s only heard on rough road services and not there at all on smooth roads. The steering is precise and no noticeable play.

As an example It totally sounds Like a loud clunking noise similar to a strut knock or top shock mount knock if it was a typical car.

I’m at my wits end with this car and this issue, any guidance or anyones past experience on something similar is most appreciated.

steamship 29th May 2022 03:37 PM

1 Attachment(s)
I've read multiple posts from people having this same knocking issue and they seem to have replaced everything to no avail. Two specific things that are mentioned are the ARB bushes and the 42mm inside the front strut.

You mention about replacing the stabiliser bar so that would rule that one out. That leaves the strut itself. The nut in question is under the grommet marked as #4 in the attached image, with the comments being that it may have worked loose. Having replaced everything else, it's worth investigating.

Prefferle 29th May 2022 03:59 PM

Quote:

Originally Posted by steamship (Post 169844)
I've read multiple posts from people having this same knocking issue and they seem to have replaced everything to no avail. Two specific things that are mentioned are the ARB bushes and the 42mm inside the front strut.

You mention about replacing the stabiliser bar so that would rule that one out. That leaves the strut itself. The nut in question is under the grommet marked as #4 in the attached image, with the comments being that it may have worked loose. Having replaced everything else, it's worth investigating.

Thanks Steamship, I thought as much initially and sent back the new strut on warranty and they replaced it free of charge, same noise. So with my original old strut, then with the new strut then with another new strut same side same noise.. frustrating to say the least… cheers,

mcs 30th May 2022 12:51 AM

After yesterday's 300klm journey by car also developed a knocking noise when the wheel was turned. I think this unloaded and reloaded the sway bar and therefore the end links.

I am going to investigate this tonight. I have replaced the sway bar bushes, so I will making sure they are in the right spot and havent slipped.

A good idea is to eliminate the sway bar by unbolting it, and taking the car for a drive. If the knock is gone, you have narrowed your items.

Prefferle 30th May 2022 01:58 PM

Quote:

Originally Posted by mcs (Post 169852)
After yesterday's 300klm journey by car also developed a knocking noise when the wheel was turned. I think this unloaded and reloaded the sway bar and therefore the end links.

I am going to investigate this tonight. I have replaced the sway bar bushes, so I will making sure they are in the right spot and havent slipped.

A good idea is to eliminate the sway bar by unbolting it, and taking the car for a drive. If the knock is gone, you have narrowed your items.

Hi MCS,

I have replaced the complete ARB / anti-sway bar along with drop links in my quest to finding this noise.
Cheers,

steamship 30th May 2022 03:32 PM

1 Attachment(s)
We're running out of things to check. Looking at an image of the suspension, you seem to have worked on almost every single nut and bolt. Grasping at straws here, but any likelihood that the bolt (#2 in the attached image) could be loose?

mcs 30th May 2022 09:26 PM

Quote:

Originally Posted by Prefferle (Post 169862)
Hi MCS,

I have replaced the complete ARB / anti-sway bar along with drop links in my quest to finding this noise.
Cheers,

In my car, one of those end link bolts in the sway bar keeps loosening over time.

I literally removed the sway bar and the noise went away. I put it back in and retorqued the bolts and it is fine now. I may have to use some thread locker.

Mike

Prefferle 30th May 2022 10:18 PM

Quote:

Originally Posted by steamship (Post 169865)
We're running out of things to check. Looking at an image of the suspension, you seem to have worked on almost every single nut and bolt. Grasping at straws here, but any likelihood that the bolt (#2 in the attached image) could be loose?

Hey a great point - I’ll be checking that bolt next. What I was thinking was that the axle may be worn and causing that noise. There is no clicking when cornering though which is one sign of a worn axle cv joint… it’s certainly one of the few last possibilities…

Cheers

Prefferle 30th May 2022 10:20 PM

Quote:

Originally Posted by mcs (Post 169873)
In my car, one of those end link bolts in the sway bar keeps loosening over time.

I literally removed the sway bar and the noise went away. I put it back in and retorqued the bolts and it is fine now. I may have to use some thread locker.

Mike

Some thread locker would be a good plan however make sure that you are torquing those bolts correctly.

Cheers,

mcs 31st May 2022 01:28 AM

Quote:

Originally Posted by Prefferle (Post 169875)
Some thread locker would be a good plan however make sure that you are torquing those bolts correctly.

Cheers,

40nm +90degrees


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