Clutch Or Gearbox

[top_driver]

hopefully this will be the last problem with car, for a while (previous posts) i said the car sounded rough thinking it was the engine, but now i know for sure it is coming from clutch or gearbox. and with the noise, there is like a quick-fire banging and once the car is driving when i change gear and engage them, there is a bang and when i reach a certain speed there is a deep drone travelling through the car. it is a new clutch, with release bearing and new flywheel, i just changed the gearbox fluid tonight with a gear protecting additive

[SlackAlice]

Still the BMW and rear wheel drive?
Check all engine/gearbox mountings for security and that they are in good condition. Check the propshaft U/J's for wear, there should be no lateral movement detectable by hand.
Not sure if it's fitted to a BMW but check if you have a shock absorber fitted to prevent/reduce engine rocking on acceleration/deceleration and that it's all ok.

[top_driver]

the rubber coupling and centre bearing were replaced, you can also hear a scrape spinning sound when half of the clutch, say at the traffic light

[tonyav]

Is the clutch working ok though when you pull away or change gear ?.

[top_driver]

It isnt smooth, and it sometimes sllips, i wouldnt mind but the clutch alone cost me 600

[Graham-W]

Does your car have a "dual mass flywheel" and if so, was this changed along with the other clutch parts. You description sounds like a dual mass flywheel going faulty and slipping when it shouldn't causing a snatchy and noisy gearchange.

[top_driver]

Ha you must have missed a bit, it is a new flywheel. i had installed with new clutch

[tonyav]

You haven't got an oil leak have you ?, crankshaft rear oil seal ?.

[top_driver]

not that i am aware of. having said that, it is possible, is it possible the clutch isn't sitting correctly

[tonyav]

Yes I suppose it is possible.