A simple search/look would have found you this :
"Suspension knocking / clunking noises are fairly common with Saxo's... especially if the front suspension has been lowered and/or large alloys have been fitted. The noises can also be VERY frustrating!
I hope this brief FAQ will give you an insight into the most probable causes of 'your knocking', but please remember that the suspension system is a fairly complicated system, which cannot be fully described here...
First things first...
Before you begin to attack the suspension you should first ensure that the three engine mounts are not showing excessive signs of wear and that they are bolted securely in place. For more information regarding your engine mounts, please refer to the 'Replacing Your Engine Mounts How-To Guide'. If an engine mount is worn it may enable the engine to rock backwards and forwards under acceleration/braking... often causing a 'clunk'.
If your engine mounts check out OK, the source of the knocking is almost certainly due to the suspension system.
Things to check with the suspension...
There are a number of suspension components, which could be creating the knocking noises, however 90% of the time this is caused by loose wishbone mounting nuts. (lower suspension arm nuts) The wishbone mounting bolts pass through the floor of the Saxo, in the footwells... each wishbone is secured in place by two 16mm nuts.
These nuts are very simple to check... Lift the front section of the carpet after removing the necessary trim clips. You will have to make a hole in the sound proofing material, which will then expose the nuts. These 16mm nuts must be TIGHT... any play will cause the lower arm to rock.
If the wishbone mounting bolts are secure, the knocking could be caused by a damaged lower balljoint, an excessively worn anti-roll bar link rod (drop link), loose strut-top mounting bolts (13mm), a damaged driveshaft, a worn wheel bearing or one of many other less common faults...
If you are confident in replacing the suspension components yourself, take a look in the Premium Member How-To Guides section for further information... If you jack up the front of the car and try to rock the wheels at the top and bottom, this may give you an extra clue about the likely cause of the knocking.
REMEMBER:- Don't just put up with the knocking... it won't go away! Depending on which component is causing the knocking, this could be potentially dangerous to you and other people. You should never make compromises with your suspension/steering components!
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taken from FAQ quides -
http://www.saxperience.com/faq/show-...e.php?artid=86
