Suspension Knock: Sorted

[Gerrit Loubser]

I have been battling to find the source of a suspension knock on Imvubu, my Patrol, for some time now. It seemed as though it originated from the front of the vehicle and sounded like a dull knock or sometimes almost like a creak.

It was not easy to determine when it would occur. Sometimes it happened on pull-away, sometimes when changing gear and at other times when the wheels mounted an obstacle or ridge.

At one time it vanished for a long time, but then returned with a vengeance after a Moz trip and seemed to get worse and worse; on a dirt road the suspension would chatter away rather irritatingly.

After some research on the Aussie Patrol4x4 forum, the initial prime suspects were the anti-roll bar links. I removed the front anti-roll bar completely and checked all the suspension and body mounting fasteners for tightness. I was so certain that the noise originated from the front of the car (although a colleague said that it sounded to him as though it was from the rear), but it was not the case: the knock was still there.

Today the rear anti-roll bar came off as well after I had noticed that a feint knock was audible from outside the vehicle when rolling the body heftily by gripping the roof rack. Now Imvubu is quiet and dignified on dirt again.

It seems that the sealing boots that cover the anti-roll bar link spherical joints had perished, thus allowing water/dust/sand in. Then it was but a question of time until the ball joints wore to the point of having play and making knocking noises.

I am actually tempted to leave the anti-roll bars off permanently. It is my conviction that they are not that essential to safe handling on a beam axled vehicle anyway, but that a major reason why they are fitted is to minimize body roll for the sake of the occupants: humans seem to get disproportionately uncomfortable when the body rolls...

Perhaps I must get a price on those links from Nissan for interest's sake .

I was once again amazed by the ability of a vehicle's structure to transmit and amplify sounds in totally confusing ways.

[Herrie]

Mooi Gerrit - very well done

[Kagiso II]

Knapgedaan Gerrit - so leer ons anner manne ook. [Boezman het ook so 'n ge-klop-klop en da' sê ek: "Kom binne!" en da kjyj die Dwergie my skeef aan]
Ek sal mar more die ekstra bottel-jack agter die agtersitplek weer stukkie spons omsit..

[ricster]

I've noticed a similar knock on the Maiden.... Not so much on pulloff or bracking, but let me climb the slight ramp into my driveway from the street, and ....clunk ...clunk.... .... I also couldn't figure out where the hell this "clunk" was coming from. I looked at the stabliser link and noticed that the bolts were not as tight as I thought they should be. I tightened them up a bit and it seemed that the problem was cured..... then I went on one of the Nissan4x4 outings... and after some good axle twisters..... my delicate "clunk" was back.

I went to Nissan in Alberton..... wait for it.... wait for it..... Approx R 400.00...... wait for it ...wait for it.... EACH !!...... I assume this is an agents only part.

I think I'm going to remove the links to the bar, and make sure that the links are the problem. I havent checked yet but are there rubber bushes on the anti roll bar itself that might need replacing? I assume that these links cannot be refurbished.

[Peter Connan]

Hello Cedric

When you have the links in your hand, take one to Bearing Man. I would be surprised if they cannot supply new ball joints tha can do the job, but to be honest R400 for a good quality ball joint is not that bad? Unless you dropped a zero?

Cheers

[ricster]

Yeah you are right, its not that bad.... to be honest I expected them to be more. I'll try Bearing man, but the link is a kinked shaft with the balljoint on both ends and shaft fused together.... but hey.... no harm in trying them anyway.

I've got the quote in the Maiden, I'll go get it later, and post the prices.

[Peter Connan]

Sorry Cedric I was thinking of the rear anti-rollbar (my car doesn't have one on the front axle).

Piece of stainless steel and welding machine?

[ricster]

ha ha....no worries....

"Piece of stainless steel and welding machine?".... yip....always an option. Two ball joints and a steel tube threaded on the inside to get the correct length.... hmmmm..... sounds like a fun project and I won't even need to get my heavy 19-footsack welding machine out..... what type of steel tube would you recomend?

Now I'm wondering why the front links are straight and the rear have a slight "S" kink to them? What would the purpose be for that? Possibly to keep the link vertical? Why would it need to be perfectly vertical? Is it to give a little flex if under full force?......hmmmm so many questions .....so little time

[Peter Connan]

Hi Cedric

I am not sure what yours looks like, on my bokwa the rear anti-roll bar links are straight, and they only have ball joints at the bottom end, where they bolt through the anti-roll bar itself. The end that bolts to the car does not have a ball joint, it has a rubber grommet with washers supporting on both sides. a loint like that can only flex through a certain angle, so needs to be kept within those limits.

Can you take me a couple of pics?
Cheers
Peter

[ricster]

You know what?..... I've just gone and made my name .....donkey ..... There is only one ball joint (took a pic, but realised the cable to download to PC is at home), with a shaft and threaded section with the collar washer and rubber that mounts to the chassis, then rubber and collar washer with a nut to secure. ....... Sorry for the confusion.

On the weekend I was looking at my brother in laws Jeep Cherokee, and his has the kink in the shaft, and I'm still pretty sure two balljoints. He had a similar noise..... only to find out that his front propshaft "CV/universal" that connects the front prop to the transfer box had actually torn out part of the metal casing in which it sits !!! ...

Nissan prices for these links
The stabiliser link front is R 366.73 + VAT
The stabiliser link rear is R 440.27 + VAT
and excl. any discount