S40 r design notchy steering
 

Hi. My s40 has notchy steering when cold but loosens up when warm. Any ideas please?

Quite likely the steering rack is leaking PAS fluid from the gaiters at one or both ends. Once confirmed with a visual inspection you can try additive that you put in the fluid tank that plumps up the seals and will delay the inevitable. It it is this, eventually the steering rack will need to be replaced which isn't a cheap job.