I have just bought a 2008 Octavia Scout 4x4 and very happy with it.  The only concerning/puzzling thing is a whoop/drone noise coming from the rear.  I particularly notice it when turning tight circles slowly in a car park although I think it also does this at higher speeds freewheeling around a bend (according to my garage man).  However, it doesn't happen every time.  Any ideas?  Much appreciated. Thanks!

I suspect this maybe one of a couple of things:

 

1) Check there is no play in the wheel bearing. Jack up the car and try to move the wheel from LEFT TO RIGHT (horizontal plane).  If you are getting movement, that is where your drone noise is coming in.

2) Is there any rubbing occuring on the rear wheels?  Inspect the wheel and see if rub marks on the tyre itself.  If so, there is fouling with the rear wheel arch.

3) Drive train - you probably have either a HALDEX3 or possibly HALDEX4 system (4 wheel drive).  There is always drive to the rear wheels, so it is run to inspect the drive train to the rear wheels from the diff.  Any movement laterally on the drive/carden shaft would need to be attended to.

4) When was the last oil change of the HALDEX box?  If you are uncertain, it is time for an oil change. 

5) Ditto - rear diff box as well - it will need an oil change.

6) Just check whilst you are under the car if the rear springs are intact.  You will have the rough road suspension setup and I had a spring break on me around 60k.  It does happen, so check all the suspension components whilst you are there.

 

Hi, Many thanks for these ideas.  I don't know when the oils were changed so definitely putting that on the to-do list.  I did take the car to my friendly garage and they had a good look under the car and nothing stood out as being untoward but armed with your check list I'll have another look.  I'll let you know how I get on.  Thanks again!  Carl

PRobably worth a gearbox oil change too whilst you are there....at least you know the gearbox system is viable and well lubricated.

The other obvious thing that I forgot is the rear wheel bearings are suspetable to loosing their grease or being incorrectly torqued (do you know the service history??).  That is an easy fix, hence it is top of the list.  as well as the left/right movement (listening from clonks or seeing excessive moment), turn the wheel itself and if you are getting even a slight noise, it will definately be the wheel bearing....but please do go through that list.  Pre-facelifted Mk2 Octavia Scouts are as rare as rocking horse manure.

Edited 3 April, 20206 yr by varaderoguy

Differential planet gear noise, they are the only parts move only under the circumstances that you describe.

 

As you dont know the history make sure someone as stupid as me has not made the same error of draining the diff thinking it was the Haldex drain.

 

Drain the diff, the drain plug is (all too) easy to find, its at the bottom directly underneath the haldex filler (nice design VAG 🥴) if what comes out is spotless and smells like diff oil not Haldex then you can put it back in but not through the filler plug above, the diff filler is to the rear, if what comes out is just a dribble of blackened fluid then you have problems, if Haldex fluid comes out then you have been very lucky, flush the diff and refill with the correct grade of diff oil.

sounds simple but it was one I had missed - what's the condition of your tyres? old, saw toothed or uneven wear can cause noises similar to bearings especially on turning

 

 

Thanks again all - a bit delayed but is in the garage being serviced and have shared the other things to look at.  I'll let you know how I get on.  One thing that a chap at the garage suggested was possible 'axle windup' - any thoughts?

Unlikely to be Axle Windup. That generally requires locked diff's and is a result of going around offroading with permanent 4 wheel drive and no slip from the diff. It is caused when you go corners fast in 4 wheel drive mode. You gotta love random massernations from mechanics.