For a while now I have had a clonk coming from the LHF suspension. It would only manifest under certain conditions.
Previously I had placed a crowbar under the wheel when I had it on a jack to change the oil. It didn't heal itself so another look revealed movement in the balljoint area when gripping the wheel at 9 & 3 position.
After dismantling, I looked at the swivel joint as VW call it, & it all looked good. The nyloc lock nut that pulls the joint into the housing had somehow loosened or it was not tightened correctly at the factory. I have owned the car from new & never touched the nut.
I bought all new nuts as VW insists, together with a new stretch bolt that goes through the hub into the driveshaft.
The new bolt was different from the hex. headed screw that was installed when new in late '05.
I had bought the Haynes manual early in my ownership & had called for a tightening torque of 200Nm + 180 degrees.
The new bolt is 12 point 24mm but should be tightened to 70Nm + 90 degrees as far as I can tell. Can someone confirm this. Below is a picture of the two types.
VW also show the same bolt with ribbing under the flange head but wasn't available to purchase.




The image on the left is the original hex. head with a very thick washer that is captive.
The one on the right still uses a 24mm double hex socket but the 40mm flange that is forged as part of the screw would provide a larger area of clamping.