Drone coming from rear...help!

[bengie]

:iagree:

run your hands on them front to back and if it feels smooth that way and rough going back to front then swap the tyres and take it for a spin

[KenONeill]

Slightly o/t, but Bengie, have you ever seen/felt scrubbing on rear tyres? I haven't, not even on high power rwd cars (unless the owner's in the habit of doing high power take-offs). I've seen in on the fronts of even quite moderately powered cars, including my late lamented ZX, and a Sierra 4x4 V6 (putting 1/3 of power to fronts).

[andypandypoos]

if scrubbing is as you describe a couple of posts before then yes, on my focus

[bengie]

apparently on the rears its caused by braking not power

[mbames]

My octy sounded like it needed a new rear beating, but hacking it up did not reveal any with the rocking test - I even removed the rear pads to make sure.

There are two types of bearing - either the bearing by itself or a whole hub.... depends on the car as to which u need. For my 2001 TDi I needed the hub, which was about

[KenONeill]

Cheers Andy & Bengie. In this case, does the scrubbing go the other way (high end of wedge to front)?

Sorry Duke, I'm trying to get a handle on the problem as a whole, rather than just solve a specific case.

[bengie]

yeah i think so, then when at the bottom the tread has a higher leading edge that folds over. the springing out of this slightly folded edge causes the drone.

[KenONeill]

Cheers. Now I've got you, and agree with you. Before I couldn't see how scrubbing could cause a drone, cos I'd never had it myself.

[duke of hazzard]

well would you adam and eve it!!!!

the bearings are fine, ITS THE TYRES THAT HAVE LIPS ON THE EDGE AS DESCRIBED! luckily my tyres are not directional (michelin pilot exalto's) so ill swap them over and job should be a good un!

Hats off to that man!

[KenONeill]

And I've learnt something new. I'd never seen scrub as described on rears.

[bengie]

just for the records GET IN THERE MY SON!!!

HTH

[bengie]

And I've learnt something new. I'd never seen scrub as described on rears.

neither had we until we were told to check it by a mechanic where i work, we too were very doubtful until we looked and swapped the tyres over and it went away

every days a school day

[duke of hazzard]

hahaha, you do deserve a round of applause, it was my dad prompted me to check again, and hey presto! quite big too actually! i hang my head in shame for not noticing first time. was going to buy some more of the same for the front because they're due but i think ill buy another brand now.

[KenONeill]

As you might have gathered, I'd seen scrub before, but only on fronts, where the high end of the wedge is at the back normally, so it doesn't fold over making the droning sound. It was the way it had reversed itself that confused me.

[bengie]

its caused by the braking rather than accelerating that puts the wear on the other side.

duke, don't put it against the tyre's as its nothing to do with them they are innocent in this case, its caused by braking thats all and every tyre could be susceptible to the same wear

[KenONeill]

Yeah Bengie, I got that eventually! You're quite right that it's caused by braking; my exp would suggest that it's specifically caused by hard braking in turns?

[bengie]

no idea on that myself

[Goochie]

Thanks teacher Bengie!

[bengie]

no problem phil, you finished doing your lines yet?

[ap0gee1978]

yeah i think so, then when at the bottom the tread has a higher leading edge that folds over. the springing out of this slightly folded edge causes the drone.

I was once told by someone who knows far more about cars than me that this is why the tread repeat distance isn't constant as you go round the circumference of road tyres - if it were, it'd set up a standing wave around the tyre, and you'd sound like a Land Rover!

[duke of hazzard]

well, back to square one :( after swapping the tyres around the noise improved a little, 2 weeks later, back to noisy, swapped front for back and noise still coming from rear...

can someone in the know please tell me (for certain) which part number i need to buy? i reckon i can do this myself if all i need is a 30mm socket.

[cyclesilly]

Another cause of scrubbing on rear tyres is loading in the boot, my last civic estate used to lip the rear tyres if there had been any excessive weight in the boot or a trailer (or tin snail!) on the rear. rotating tyres would improve it temporarily but it would soon return.

I have recently collected my mk1 vrs from the local Skoda dealer, on the test drive they said it would have the noisy bearing changed, on collection the noise was gone, but two weeks later the drone is back and very audible at 60, difficult to test at that speed for changes in sound at strong cornering though!

Garage not given any proof of bearing change could they have just repacked it with grease?:thumbdwn:

cheers

David

[ap0gee1978]

I can't believe it - nearly 50 posts on a thread asking about a 'drone coming from the rear', and not one joke about giving the mother-in-law a lift!

[Basil]

I wonder what the rear axle alignment is like?

The fact it got better and then reccurred

suggests that the rears may not be lined up right....?