Steering wheel shaking could normally be put down to wheel balancing but when you talk about this growling it may be that you have a knackered wheel bearing/hub which can get to be quite noisy at motorway speeds. Sorry I misunderstood your earlier post when you said the thudding from rear was rythmic and varied with road speed. If you can it would be wortnwhile getting the rear end off the ground and turn wheels by hand to check for source of knocking around rear diff and prop shaft. Could also be worth having a good look at tyres for any bulges or defects. Your dry stick noise may just be the ACE. The system has a pressure control valve in the control block which controls pressure in the system. It can noticeably "sneeze" for want of a better word at times where the ace isnt having to workmuch, where no corners such as motorways. Its simply reducing the system pressure. Try leaving idling for some time and see if it happens. Control block is mounted on chassis below drivers seat

You people are geniuses. Right, will check the CV joints ASAP. Will also jack up rear end and seek out thumping noise. Will also investigate ACE, and see if the sneeze is the same thing as the stick thing. I left her idling today and could still hear the growl a bit, but it did not increase when I dry turned the wheel. So probably not PAS pump. Looking like ACE could be one of the culprits.

the ACE pump gets noisy in time if ATF was used instead of the green PAS fluid and wasn't replaced for long, people used to put ATF in as it's cheaper but IMO it must be renewed twice as frequently as in the gearbox cos the ACE pump works all the time and at much higher pressure while the gearbox doesnt work at idle