series 3 knocking from rear end

[clive V12]

Hi,
I am new to this forum and would like to know if anyone can help me?
My V12 has just started to make a knocking sound from the rear, I have lifted it up onto stands and put it into drive but can`t see anything catching,it does seem to orignate from the diff or brake area.
The sound increases with speed.
Can anyone help ?

[christopher storey]

If the sound is speed related, increasing in frequency the faster you go, but without being a heavy knock, then a likely candidate is one of the driveshaft dustshields. These should be secured by a jubilee clip, and the two halves are riveted together, but people forget to do up the clips after greasing, or the rivets rot away . You may find that you cannot reproduce the knock on stands because the droop of the suspension arms affects the juxtapositon of whatever is knocking

[clive V12]

Hi,
The noise is a heavy knocking and is speed related but not the dust shields.
Thanks for the advise.
has anybody else got any suggestions ?
Thanks,
Clive

[Heuer]

Not the same problem as this is it? http://etypeuk.com/forum/viewtopic.php?t=1109

[Aldeburgh]

As david says, sounds very similar to my problem http://etypeuk.com/forum/viewtopic.php?t=1109

You can only see it when the car is supported on the wheels... when jacked up the spring relaxes and straightens - you need an inpsection pit or a four-poster for things to be obvious.
Good luck

[clive V12]

Thanks for that info guys, I will take a look tomorrw.
Sounds like this could be the answer as I did notice the a mark on the UJ and it is toching the spring.
Let you know more tomorrow.
Thanks Clive V12

[clive V12]

Hi Guys,

Thanks for the advise, you are totally correct.

ONE BROKEN SHOCK !

I will now start ordering the bits to replace all shocks,springs,discs and pads.

Thanks again,

Clive V12

[e-bygum]

I have not heard that broken rear shocks was a problem on S3s and we have two reported in as many weeks!
It would be interesting to know if there is anything common in these instances, i.e.

-what type/make of shocks were they?
-how long had they been in use?
-what type of driving had they experienced (hard driving on twisty lanes, track days etc.)?
- were you aware that something had gone wrong at the time of failure?
- are there any modifications to the rear suspension etc?

Just interested.
Pete

[clive V12]

Hi Pete & All,
information so far on broken shock;

I think it has been on the car fron new and therefore standard, no mods,
I have driven the car quite slowly just the odd fast pull away,
The knocking was the first sign of the problem,

I will update you when I strip the back end in a couple of weeks.
Hope this helps.

Clive

[e-bygum]

Thanks Clive
The shocks don't owe you much then.

[Aldeburgh]

Couldnt tell if my broken shock was from new but I doubt it as the suspension had been generally gone over during a reasonably thorough restoration about 5 years ago.

There was no bang when it went and not much difference in the driving behaviour immediately afterwards apart from the knock... but I was not hurling it into corners admittedly. So far as I can tell it went during overtaking at about 60mph.

Harry at Etype uk fixed the problem for me with his customary efficiency and said he had never seen a shock fail like that before, arguing that it is far from a commonplace occurence... intriguing coincidence to see two like that so close together.