Clonking noise
 

My D3 has out of the blue decided to develop a clonking noise from the NSF, low down close to the floor. The sound only occurs on bumpy surfaces, on smooth roads its not really apparent. There is no pulling in the steering or clonking /knocking if you turn the steering wheel whilst stationary.

it happened suddenly, on Sunday it was fine but now its quiet obvious. Given that I live on a farm and drive offroad down a mud track to get the house maybe something on that front has caused it.

I am guessing the lower suspension arm on that side, would that be a good diagnostic?

Either one of the two lower suspension arms, or before you replace those which are expensive, check out the anti roll bar bushes - if they are worn badly then they could cause a clonking noise where the bar isn't protected any more.
If it's the anti roll bar bushes then you will have to replace the whole bar at about £120 iirc

Could be the C link?

I suggest having a look at the Drop Links/C-shaped links that are attached to either end of the Anti Roll Bar unless they have been replaced recently. I had them replaced twice (£65+vat for the pair from Audi) on my old D3. They seem to only last 70K-80K miles. They are easy to change. See Photo.
The front lower arms with the track rod ends were also replaced once over 223K miles/5 years.
The 2 bushings on the centre section of the Anti Roll Bar also cause the knocking you describe but you would have to replace the complete Anti Roll Bar (£146+vat) as these Bushings are not available separately.
One way to eliminate some of the options is to temporarily remove the Anti Roll Bar (Only 4 Bolts) and road test without it fitted. If the noise is still present, its back to checking the upper and lower arms which are all mega ££ for Genuine parts.

I think this is my car rewarding me for 2 years and 18K miles of ownership, I've long since stopped doing my own maintenance so I'll get it booked into a local garage to check all the lower bushings.

I know the lower arms are expensive, I had one replaced on my old D2.

Common fault on the front is upper [inner] side... but as others suggested it could be related to several points incl. notorious [as in annoying] anti roll bar bushes.

I'd suggest to take it to a 'decent' mechanic to have a look and inspect this for you and isolate an issue... FYI, I recently replaced all of them on mine and you'd be looking @ @450 for parts [OEM Lemforder] + 100ish for labour. And you'd need tracking so all in all should come to around 700ish GBP.

Expensive but worth the job if you are planning to retain the car :).

Hope that helps...

Well the old girl is now fixed, the fault was caused by the most stupid of things.

Garage did a road test, then it came back and went on the ramps. After lots of prying and jiggling they discovered that one of the drop link bolts was loose. Retightened bolt and all back to normal.

good news and a nice and easy fix:):)

Yep, and its been fine ever since.

I've just replaced my anti roll bar and the final small knocks have all disappeared and the steering feels tighter and all I hear now is tyre noise if anything at all so all sorted here too +++