Full 2006 Z4M Refurb & Some Questions Please

[ed80]

Not sure if these are still for sale, but probably worth a PM: https://z4-forum.com/forum/viewtopic.php?t=150138

 

[jontZ4M]

ATE (OEM) front brake discs are £262 per side at Car Parts 4 Less with their current discount code: https://www.carparts4less.co.uk/brake-discs
That is a pretty decent price. Only buy ATE or BMW discs for the M.

I had a noise coming from the rear brakes on mine too, it wasn't the backing plate, but a tiny bit of debris caught under the brake hat that was catching on the handbrake shoes. It was a very loud and annoying noise for such a small piece of debris! You should be able to tell it's that rather than diff noise because:
1: It will obviously be louder on one side than the other (diff noise is central)
2: It will be external, and get louder with windows down
3: The noise won't change when accelerating vs coasting (diff noise does, I have subsequently discovered)

Removing the disc and recleaning everything fixed it.

Thanks Ed. Will investigate based on what you said.

I've been thinking about it while supposed to be doing my day job.

I think I'm going to remove Nissan from the ramp on Wed, which is my next workshop day.

Put Z4 back on ramp.

- Regards juddering from front - before I commit £500+ to a new pair of discs and potentially ruining them, I'm going to remove front calipers and discs and just re-clean everything and make sure everything is perfectly seated. After re-assembly if the judder is still there, then it must indeed be a warped disc and I'll buy the new pair and fit.

- Regards the rear noise I'll run the car in 6th gear on the ramp(do we know how to disable the ESP in this car to allow rear wheels to spin without front wheels moving BTW?). With the rear wheels spinning I plan to hunt around underneath the rear for the sound. I can use a piece of pipe to listen into the diff etc to check for sounds. Then I plan to remove layers and run car with each layer removed to see when the sound disappears. This will identify the troublesome layer. First wheels, then calipers, then discs. If it's still noisy at this point then the noise must be from bearings or diff, as there is nothing else left to make noise.

Does that make sense?

There is just one more thing I was thinking of. That is that I've changed all bushings on the car. Could new bushings be transmitting more sound into the cabin? I've had this happen before BUT they were drift cars so it didn't matter. That said, all new bushings were OE rubber except for main rear subframe bushes which were poly. But I doubt poly transfer sound to any real degree.

 

[jontZ4M]

Not sure if these are still for sale, but probably worth a PM: https://z4-forum.com/forum/viewtopic.php?t=150138

Obviously I'd rather not pay full price BUT I worry that buying used discs may not be the correct step, as I've got no assurance that they don't have a warp also.