Hollow thumping

[triumphtigger]

I have a 2006 4x4, pre-scout TDI

 

Around this time in 2012 it developed a dull, hollow thud from under the left side of the car. At service in Spring they replaced a lot of the front suspension, yokes and bushes mainly (I'm not that conversant with modern suspensions). Now the sound is back, noticeable only when I drive over uneven bits of road. Like before, I can't tell if it is front or back. The sound is hardly noticeable. My wife can't hear it - but I used to work on a marine diesel test bed, so I guess my ears are tuned to such things.

 

Years ago, when I could actually fix cars myself, I would have been sure the noise was from worn shocks. Now I'm not sure. Any ideas?

 

I'm wondering if the cold weather has anything to do with it?

[billywhiz040480]

If they haven't already been changed then I'd suspect the anti roll bar bushes or drop links, mine are all being changed in the new year when I get my eibach b12 kit fitted.

[gadgetman]

If at speed, did they refit the underside engine cover properly?

[triumphtigger]

Not only at speed, every bump. Can't hear it with the radio on, even low, so it can't be that loud. Strange it's only the left side, and strange it stopped when they did the front anti roll bar bushes and almost everything else at the front end (springs too). The sound does seem to be exactly the same as before, and from the same place - though I can't pinpoint it. Middle, rather than front or back - but I suppose it might be transmitted noise from the source.

 

Is there anything in the front that might have changed since they fixed it all? We have some pretty bad roads around here, but I don't recall hitting any big potholes.