Z4MC - Knocking noise from rear suspension

[BensZ4MC]

Hi,

Have noticed a knocking noise coming from the rear suspension at speeds up to 50 MPH.. any ideas what it could be?

Cheers B

[JDMc]

BensZ4MC said:

Hi,

Have noticed a knocking noise coming from the rear suspension at speeds up to 50 MPH.. any ideas what it could be?

Cheers B

Snapped rear coil spring?

Seems to be a common issue. Failing that it may be a worn bush.

[Banus333]

BensZ4MC said:

Hi,

Have noticed a knocking noise coming from the rear suspension at speeds up to 50 MPH.. any ideas what it could be?

Cheers B

I have the exact same problem on my Z4MR. It comes from the OSR on bumpy roads & at <5MPH reversing out of my garage or turning into my drive at minimal speed. The local Main Dealer had the car for 2 days last week & claimed they had re-torqued all of the rear suspension mountings - but the noise is still there. Driving me nuts!!

One assumes that as the main dealers have inspected the car that it is not the common coil spring breakage. Therefore it can only be a loose cable in the OSR knocking against the inside rear wing, a duff OSR shock absorber or duff rear anti-roll bar mounts... I'm not impressed by the dealer just leaving the problem.

[physprof]

check that the retaining clip that holds pads into caliper is in place (it is very obvious if you look at the brakes) - I had knocking and rattling (a bit like a loose heatshield underneath) that was most common on a series of short bumps in road.

had it in a dealer last week and the claimed to have fixed the heat shields underneath - drove out and within 3/4 of mile it was still there. back in yesterday and this time they noticed the missing clip - all seems fine and well - noise gone.

Kicking myself that I didn't notice the clip missing but then again you'd have though they might have seen it on first dealer visit...
my pt no. from realoem is 34212282198 just google the part no.

However to top it off they caused a cosmetic problems back in next week to get that remidied.... dealers sometime you have to wonder.....

[fridaypassion]

Snapped coils seem to be quite common.

This might be a really stupid question but its something I've noticed is that when you have anything in the boot thats even remotely loose it bangs about like anything probably due to the solid floormat. Just a thought!