knock noise from front offside, front nearside and rear offside

[Rick-sta]

Hi all,

My Typhoon has decided to develop some knock sounds in the last few weeks. Doesn't get used much these days, especially in the last year and a half or so.

Everything was fine and perfectly smooth until a few weeks ago where I'm now getting a pretty loud clonk mainly from the front offside, but sometimes from the front nearside as well. And I'm also getting another loud clonk from the rear which sounds like it's coming from the rear offside.

The knock sound is 1 single knock at a time (sounds like as if someone hit the subframe with 1 firm tap with a hammer). The front knock from the offside and nearside and the knock from the rear offside all do it when I pull away or if I'm turning at low speeds. It'll also do it when I accelerate regardless of what speed I'm doing. For example if I'm doing 50mph and I lift my foot off the accelerator for a second and then apply full throttle it'll make one single clonk at the moment I accelerate. It doesn't make the knock/clonk noise every time either, I'd say it does every 1 in 3 times.

The knocks are loud enough to be heard from outside of the car when standing near it whilst it drives past. The weird thing is the knock seems to sound like it's coming from a different area each time (for example the one coming from the front offside sometimes sounds like it's coming from low down behind the wheel, then it sounds like it's coming from much higher up near the bonnet, then it sounds like it's coming from under the floor on the sill between the driver's seat and the boot release button.

These knocks are different from what I've had before on any 75 or ZT, as these don't happen at all when driving over uneven or rough surfaces. And whereas knocks that I've had before due to drop links or wishbone arm bushes usually make more of a wobbling knocking sound when driving over rough uneven surfaces (or when pulling away or braking when the rear wishbone bushes are shot), these knocks I'm getting are only ever one single knock.

I've had a good look underneath with the car on the jack and there is no play what so ever in the front wheels or the rear wheels. The springs all round look fine and can't see any sign that they've snapped anywhere. The front drop links were an advisory on the last MOT due to the dust covers deteriorating but the drop links themselves appear to still be solid, there doesn't seem to be any play in the anti roll bar with the front wheels off the ground. I'll be replacing the front drop links soon anyway though due to the advisory.

Can't see any play in the wishbone arm bushes or the track rod ends.

The wishbone arms and bushes were replaced about 6 or 7 years ago with good quality ones from DMGRS and have done around 45k miles I recon. Front and rear shocks were replaced with the springs (have motobuild springs which were fitted about 6 or 7 years ago and have done around 50k miles).


Any suggestions on what it could be or what I should look into?


Cheers
Rick

[cbr1100xx]

Exhaust possibly, mine knocks just the once on start up and then nothing for the rest of the journey.
Its knocking on the rear valence behind the bumper.
Not sure if the sound would travel around from front to rear ,but worth a look

Stan

[bl52krz]

Hi Rick. Have you ever had the bearings replaced on the top of the front shockers? The rear could be the bushes on the trailing arm.

[Dawn]

I'm having the same problem, a random noise I can't even tell where originates, engine mount and drop links are pretty new, and no set pattern. I can't see anything either. Pretty sure it's not top mounts either as I've had that before. I do have a SS exhaust and am wondering if its not 100% perfect fit?

[steady eddie]

I would check the lower arm rear bushes the wifes tourer did that at the front end, bushes did not look too bad but I changed them and all was fine.

[stevestrat]

I had an exhaust drop for some reason, just enough to bring the exhaust tunnel cross braces within range of exhaust movement. Never got to the bottom of the reason for it dropping, my mechanic mate ended up making an additional support.

[trikey]

I'm going with drop links, I had a knock on Deb's ZTt and discounted the drop links as they were not that old, i swapped them over and now all is well.

[Rick-sta]

Thanks for all the suggestions.

It's not the exhaust for sure, had a look at that. The typhoon has a custom stainless manifold back system and everything is very sturdy and well away from anything it could knock against.

The front drop links need changing anyway due to the dust covers deteriorating, so will do that soon and see if that helps at all.

The top mounts haven't been done on this one whilst I've had it, but I've had top mounts fail on our 75 and that was making all sorts of creaking noises and knocks when steering lock to lock. The typhoon isn't making any noises at all when steering lock to lock. I seem to get the single knock noises when the weight of the car shifts to the left or right when turning or when accelerating in a straight line.

I'll have a look at the rear arm bushes.

[OddSox]

Deffo the Front near Side Wishbone ball joint. Don't forget, sounds can travel through the chassis like you have never known and make all sorts of sounds vibrate through the entire car.

It's not the drop links or top mount's. You would have indicated a different sound pattern. Also it's not the REAR bushes. Totally different fault.

The wishbone ball joint is the culprit, given your explanation.

[bl52krz]

Originally Posted by OddSox

Deffo the Front near Side Wishbone ball joint. Don't forget, sounds can travel through the chassis like you have never known and make all sorts of sounds vibrate through the entire car.

It's not the drop links or top mount's. You would have indicated a different sound pattern. Also it's not the REAR bushes. Totally different fault.

The wishbone ball joint is the culprit, given your explanation.

Do you mean the joint that is in the wishbone that fits in the subframe?