Well after Full 9 year Service, + odd bushes replaced, proper coolant replacement new filler cap ext. and an invoice for £750.00 today, Was given the results of the knocking sound, LeeT5 you were in right area, but not prop shaft, but Bevel Gear Issue, they could replace sleeve only i think, but have authorized everything to be replaced which will cost another £1400.00 so this week my S60R is gonna cost me over 2k, i have also gotta list of other things to work my way through but not immediate, they did say it was a nice car, but previous service history i know wasn't great, i guess saving grace is that this is one big issue that will get sorted now. Issues with regards to the oil leak/burning i think is probably resolved, the previous service before my time didn't put the right oil filter on the car, which may have contributed to this, but will keep an eye on levels. Its all down to experience, i do think after a another £1000.00 for discs/ pads, other bushes, i will have a car that will be trouble free for the next 30k or so, just paying for it now unfortunately