so since I've purchased my car it has had the following replaced

rear discs & pads and calliper carrier
lower wishbones
front balljoints
front ARB bushes
AND ITS STILL KNOCKING

whilst in the garage to have all the cambelts and oil pump etc changed i asked them to look over car as it rides very hard teeth shattering hard result was it needs 3 new shock absorbers these are being replaced under warranty hopefully but I'm wondering is it common for the shocks to go especially 3 of them as i said above its still knocking every now and then at low parking speeds could this be attributed to the shocks or am i set to change more suspension parts

now the main concern when i get to over 50mph i get rather loud humming from the front end/centre of car this is getting progressively louder but at 80mph the noise seems to quieten down a touch when its in having the shocks done I'm gonna ask them to investigate this noise obviously I'm just wondering if anybody has any ideas I've searched on here and seen a few similar things i.e. transfer box etc but thought id ask
it makes the noise under acceleration and when i let my foot off the gas the noise is still there until my speed drops below 50mph

Whine noise is probably diff related however I'm not sure whether front or rear. Possibly front if you can hear it from the front. Thats where I'd start anyway. I'm not Fat. RRS TDV6 HST.

1. Diff noise would usually vary between power-on and power-off conditions.

2. Any chance they've disturbed anything that is vibrating against the chassis/bodywork. Over-tightened / incorrectly fitted suspension bushes

3. Over-tightened alternator / fan belt

4. Alternator / water pump bearing

5. knick in fan blade.

6. Wheel bearing - usually the sound varies with cornering.

Just a wild guess...

To change some of the parts mentioned it would have been necessary to remove the thick metal engine undertray which is retained by quite a few chunky bolts and nuts. It would be typical for a careless fitter to (a) forget to tighten the retaining bolts when refitting it (b) break or lose one or more of the bolts (c) cross-thread one or more of the bolts so it appears tight but is in fact loose.

Any of those could conceivably cause a vibration/hum that is speed related? 2008 MY Java Black TDV8 HSE

thanks for all your suggestions the suspension work was carried out by the small dealerships mechanic that i purchased the car from and i have a complete lack of faith in him got my car back covered in pastry were he had been eating croissants or something similar in my car so when the car goes to MY garage for the shocks and full service i will get them to check over all of his work how lovely would it be if it was just a loose under tray