S40 V40 Cars: Perplexing noise with wheel movement VIDEO

[captainbrown]

Hi All, hope I'm doing this right, I'm new to forums in general.

I have had an immaculate 1999 Volvo V40 2.0 Petrol for nearly a year now. I drive about ten miles to work and back every day, about half of which is in heavy traffic.

There is a noise coming from the front end of the car, I think more on the driver's side but can be heard from the passenger side too. It sounds a bit like an old washing machine motor (SEE VIDEO LINK - listen carefully.)

The fluctuation in volume matches the wheel speed but between 20-50mph the pitch is the same, slows down when the speed drops under 20mph and stops at 10-15mph.

When driving away the sound starts only once I reach about 35mph, and doesn't go away at all until I slow right down. Often it comes back when I speed up again, but at a different volume.

It is unaffected by acceleration, braking (including emergency stops in the wet with ABS), steering, clutching, changing gears, weight in the car, tyre pressure or engine speed. The tyres are wearing evenly. The ABS rings look fine and there have never been any warning lights of any kind.

I have tried everything I can think of but I have absolutely no idea what this is and I'm at my wit's end. My father was a mechanic and has no idea, I have never heard a car make this sound before except when the alternator is failing, and then obviously it changes with engine speed not wheel speed.

HELP!

https://photos.app.goo.gl/uu6aBbwFtkD1YA3C9

[captainbrown]

Anybody have any ideas? Any suggestions are welcome. I'm getting pretty desperate now, it's annoying the hell out of me.

I just got under the car to inspect the driveshafts again, all looks fine, no grease escaping or excess wear. I sprayed everything with WD-40 in case there was a seal or something making a noise but to no avail.

[bobthecabbage]

Can't really think what it could be. Wheel bearing? Cable tie rubbing on something? Gearbox, clutch? Obviously gearbox/clutch problems should alter with clutching in and out and putting in neutral etc.

Does it happen in reverse?

Does the driveshaft have a bearing on it?

If it sounds like an old washing machine with bad bearing (which it sort of does) perpaps it is a bad bearing somewhere?

Have you checked the gearbox oil level?

It is a mystery and I don't think anyone will be able to solve unless they've had the same problem! Short of tying someone to the bonnet whilst you recreate the problem I don't know what you can do!

Can you jack up the front and spin one wheel at a time to see if its one side or the other?

[pierremcalpine]

Nah, I don't think that's a bearing. Sounds more like a PVC liner or rubber hose rubbing up against wheel, axle or aux belt. Maybe the force of the wind pushes the piece up against something so that when you slow down it returns to its correct place...Take a good look at all the undercarriage plastic protector plates and shake them around to make sure they are sitting firmly in their clips.

[upv5]

Difficult to judge from the video but have you checked for small stone or debris caught between disk and the back plate or even the back plate slightly touching the disk.
Back plate is easily bent if some one has balanced the caliper on it when changing pads or levering a stuck disc off when replacing.

John