S60 knocking/clunking noise fix?

[D5Russ]

I've finally managed to have a proper investigation today as to what's *still* causing the noise.

After a bit of investigating, this is what i found:


I've since removed the broken bracket and it appear to have been rubbing against the lip of the cat/silencer, which i'm really hoping is the cause of the noise.



The gearbox seems to have been contacting the rubber buffer:



I didn't measure the gap but i can't get a finger between the buffer and gearbox.

I also managed to test both vacuum engine mounts with vacuum pump. The front mount builds up to around 20hg but drops back to 0hg within 10 seconds.
The rear mount i was unable to test as the plastic pipe connector had already been broken off and there is no way of reconnecting the vacuum pipe.

It does look past its best however:

[Longhouse21]

Don't want to be a doom merchant, but that first picture looks like you have an exhaust problem that has been seen on these cars before. On the elbow from the turbo to the cat it looks like you have the start of a fracture - the carbon deposits on the support look to me to confirm this.
They can be welded. Don't be tempted like I was to replace the exhaust section with a pattern part. If it can't be welded, might be best to replace with a good second hand section. Check someone like Huddersfield Volvo (who I believe will post) or a more local Volvo breaker.

[D5Russ]

Originally Posted by Longhouse21

Don't want to be a doom merchant, but that first picture looks like you have an exhaust problem that has been seen on these cars before. On the elbow from the turbo to the cat it looks like you have the start of a fracture - the carbon deposits on the support look to me to confirm this.
They can be welded. Don't be tempted like I was to replace the exhaust section with a pattern part. If it can't be welded, might be best to replace with a good second hand section. Check someone like Huddersfield Volvo (who I believe will post) or a more local Volvo breaker.

Yes I did notice the fracture. I'm going to remove that section and weld it up along with welding the support bracket back on.

Is there a common cause of exhaust fractures on these cars? I thought that perhaps the rear engine mount had gone on mine and that was the cause of it and the knocking noise.

[Longhouse21]

I don't know of a particular common cause. When mine failed both front & read mounts where in OK condition, the lower & upper torque mounts had been replaced previously. The only mount that may have been suspect on mine was the one under the crank pulley. I eventually replaced the two vac mounts and pulley mount some time after the failure. The after market exhaust sections I used failed on cat blockage.

[McGandalf]

Did you manage to definitively trace the source of the noise/fix the noise? Hard to tell from posts above.

I have a similar issue so would be interested to hear.

[simonwedge]

I also had a similar issue and it turned out to be the very rearmost exhaust mount that had broken and was allowing the rear silencer to move about and hit the floor of the car sometimes. You can buy replacement mounts for this on ebay.

[D5Russ]

Originally Posted by McGandalf

Did you manage to definitively trace the source of the noise/fix the noise? Hard to tell from posts above.

I have a similar issue so would be interested to hear.

Not completely. Removing the broken exhaust bracket has stopped the main loudest clunk on acceleration but there still is a constant clunking at low speed.

I'm now getting a clunking and groaning noise when turning into parking spaces, so I'm going to replace both strut top mounts and the top mount bearings. Hopefully that'll cure the noises.

[D5Russ]

At last i have finally found the cause of this noise....

It was discovered today by the mot tester, the driver's side lower ball joint, it was completely knackered.

What was strange though was that it only showed signs of wear by leavering the hub up and down with a pry bar. I had previously tested for a worn balljoint by jacking the car up and rocking the wheel up & down and side to side but it was rock solid?

In the end i replaced all the engine mounts (both vac mounts too), both front shocks, top strut mounts and bearings, both arb drop links, both track rod ends and got the downpipe bracket re-welded and the crack welded up and it was that £20 ball joint all along

The car does drive far better though

[petey]

Ah, when the weight’s on the wheels, the load path is totally different and that’s why MOT tests are conducted on hard 4 post ramps so that the wheels are in their natural position. Only then will the ball joint be in its normal portion of its travel curve, and only then is the lower wishbone not pulling it in, taking up all the slack.

[2.4TSE]

I wish I had seen this post earlier as I could have helped; sorry about that!

My right hand drive V70 2.4T also had an occasional clonk, in my case when turning left or under rapid suspension deflection such as a deep but rounded ripple in the road rather than a pothole. The clonk appeared to come from the right hand side of the car, both as experienced as the driver and when sitting in the front passenger seat.

Proving how sound is conducted through metal structures, the cause was a worn *left hand* steering ball joint - though yes, both sides were changed whilst at it.

Glad you're now sorted.