I have this wierd noise on my XF

It does not happen all the time - its like a low wind type of noise it goes away when i put my foot on the brake

The rear is a disc brake LSD

Handbrake disconnected too - still does it

I have this problem as well. I've been told a few theories as to what it might be.
1. The calipers dont release the brake pads enough and they are grinding. When you apply the pedal it shuts up cause your pushing the pads back hard against the disc.

2. The pads haven't bedded in properly. I just changed the rear of my wagon to disc brake lsd and slowly the pads are shutting up.

Any other ideas?????????

Cheers

Does the noise increase or decrease when you swerve the car left our right ? Which side makes more noise when you shift the cars weight to it, if the noise increases then you may have a warn wheel bearing.

Both of mine did it at the start but now only the left rear does it. It doesn't matter if you turn left or right the noise is the same. I dont think its the bearings becasue mine were checked before the diff went in the car. If it were the bearings wouldn't it do it all the time and not just every now and again.
Ive never had a worn bearing so i dont know what it sounds like or how they act.

Cheers

Have u checked the pinion and carrier bearings.

Assuming its no handbrake noise, bearing noise, tyre noise etc.
then it has to be the centre making the noise.

What sort of LSD is it ? clutch pack. Sometimes they make a sound when they have incorrect oil, low oil etc.

There is an oil additive that you can get, it was release for au's that stops lsd noise, change oil, add the additive to it, be careful not to get that s**t on your clothes, that s**t stinks. then go to an open car park and do some figure 8's to get that s**t in between the clutches, and i don't mean smoking figure 8's cause that doesn't work, the clutches are locked up. is has to be when there is no torque through the drive train other wise the ls is working.

Muff

my mate has a zl fairlane and it has a whinding noise in the rear, he replaced the engin mounts, gear box, tail shaft, rear discs, calipers and still didndt get a result, i personally think the dif may not have enough oil in it or its on its way out

i also have a similar problem on my xf, but the noise is like a ticking noise. i goes when you put yourfoot on the break and when you hit about 50 k, i am occurs on the front L & R wheels.
Its not the bearings could i had them replaced.

any suggestions?

I also had a ticking sound coming from the rear end of my ZL ... I thought it must be the Diff starting to go and got another rear end put it in. Guess what the noise was still there!

I removed the rear calipers and found the little metal tabs to hold the brake pads firmly in were missing (not even mentioned in the manual) ...

Replaced them and suddenly my ticking noise was gone.... s**t part is that the new rear end isn't even LSD ... so I'll be on the lookout for another one in good nic. ...

I'd replace the oil on the diff also.