Knocking noise after new tyres

[M3X3]

Hi everybody, this is my first post!

I know there is lots of info on this subject on the net but I hope you don't mind giving me some advice!

My wife has a 2004 X3 2.0d sport. Rear tyres 255/45 R18 and fronts 235/50 R18 All Dunlop SP01 star marked. Ordered new rears from blackcircles and fitted by local garage 3 weeks ago. Since then there has been a real knocking noise from the rear when stopping(almost 3 knocks when coming to a stop. Sounds awful!) and moving slowly in traffic. Also it doesn't sound right when traveling at speed.

Could it just be the tyres? There was never this sound before the rears were changed so it seems to much of a coincidence! When the fronts were changed last year there was never this problem?

I confirm they are all star marked (I've been out and double checked again tonight!) and the fronts still have a good amount of tread on them.

Your thoughts if you would be so kind. Thanks in advance

[Pinewood]

It sounds as if your front tyres are more worn than you originally thought. This causes an inbalance as far as the transfer box is concerned.  I would change the fronts at the same time.

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