Knocking on steering after M'way driving

[thegers]

Hello guys
My W202 C250td Estate has no noise with the steering on regular town driving but take her out on the motorway and she develops a terrible knock at you feet when you turn the wheel (left or right). Can be felt under both right and left footwells.
Any ideas? Mechanic at a loss as he always sees it without the drive to Glasgow and back! Grrrrr.
Many thanks in advance....

 

[wireman]

I take it that this is after some motorway distance so perhaps it is a steering component that clonks only when hot, there are the knuckles at the ends of the drag link and track rods, the idler arm bushes, the flexible coupling on the steering column, the steering box (expensive bit), and the damper (cheapest bit) any of which may be the culprit along with any of the bushes in the front suspension.

My first guess would be the steering damper, it could be taken off and the car road tested.
The steering behaviour will be slightly adversely affected without the damper fitted, the car won't feel as nice to drive.
The damper should offer considerable resistance to extension and compression by hand, if it does not or is not smooth in operation fit a new one regardless of its being the source or not of your clonk.

 

[thegers]

Hi Wireman

Sorry for the late thanks - posted problem then my laptop went t**s up!
Seems a case of deduction so I'll start my Pole off there. Just thought I'd ask in case there was a common thing I didn't know about!
Thanks again for the reply.

BTW W202 not a patch on the W124!

Thegers