Rear wheel wobble and noise at certain speeds

[richardsfavorit]

Im posting on behalf of my dad, he has a Mk2 56 reg Skoda Octavia 1.9TDi Ambiente and an ongoing issue with road noise and wheel wobble (intermittently) from the rear of the car.

The car has done 138K.

 

The noise is pretty consistent, I mentioned it to him last year after we came back from France and said it sounded like a wheel bearing. He took it to the garage he uses (independant local garage), they said they couldn't find a bearing issue. If there was a bearing issue it would have failed the MOT he had recently they advised.

Dad said he had looked around the net and lots of Brisky Octavia owners said road noise from the rear of the car can be an issue and is just the way it is.

 

After a bit longer - December last year, on the way to Bristol the transaction control and ABS lights came on whilst we were down there. Scanning with VAG COM the following day indicated a possibly mechanical failure at the back of the car.

The garage had the car back and changed a rear hub, resolving the issue with the ABS and transaction control lights. He asked me if I thought the noise was there when I was in the back and I said it was.

 

The other problem has been intermittently, on a straight smooth road, there is a wheel wobble / vibration felt from the rear of the car at around 60mph.This doesn't happen all of the time!

 

The noise (which to me sounds like a bearing) is still there. It is not to the level where I have had bearings fail and make a noise above 20mph and be deafening at 70mph. It is there above 40mph.

 

He drove it 100 miles yesterday and said the wheel wobble didn't happen. I am a bit lost with this one. The garage haven't had it back again.

I have offered to change one of the alloys to a spare for him and try it out to see if it resolves it, also ruling out a tyre / wheel or balancing issue. Plus I can see what the hub is doing when the car is jacked up.

Further to this he is meticulous with checking over the car each weekend, tyre pressures etc and looks after the car with regular servicing.

 

Has anyone had this happen of any thoughts? Thanks in advance.

[andyoctavia]

I would guess that the only way there would be an MOT failure, would be for noticeable play in the wheels when jacked up, plus a rumbling noise when spun. Do they check for that though?

The only wheel bearings I ever replaced were on an Alfa (rears), and they were a real pig to do. After changing them though the car was really quiet to drive.

Is it possible that the hub nuts have not been torqued up?

[nickguzzi]

The type of rear wheel bearing used makes it hard to tell just by manually grabbing the wheel if it is worn or not.

Usually, if wear is the problem, the bearing will fall apart when stripped out.

It may or may not be the problem.

The MOT would not find anything other than a grossly worn bearing, so the advice of the garage is suspect.

 

A more common cause of rear end noise is "sawtoothing" on the rear tyres, this sounds so like a wheel bearing. 

The inner edge of the tyre wears into a sawtooth like profile due to the geometry of the rear suspension. 

There has been a revised setting of the rear suspension around for a while now. 

This is rectified by a proper alignment by someone who knows what they are doing.  Not in many peoples experience, your average High St tyre place.

[mannyo]

I had a whining wheel bearing in my Audi, there was no play in it all and it passed an MOT. It was only when I insisted the bearing was changed that it went silent. However I had no wobble symptoms from the back of the car.

 

Your dad may have one or more worn suspension bushes on the rear, the Octavia MK2 has fully independent rear suspension. The noise you hear could be caused by sawtoothing tyres due to the changes in suspension geometry. Such wear is not always obvious, it can be perfectly aligned when not moving but road bumps and undulations cause additional flexing in the bushes which feels like a wobble.

[radders567]

A place to start would be to inspect the rear tyres to make sure there is now saw toothing on the shoulders of the tyre ( this will replicate a wheel bearing droning noise). I would then get the rear wheels balanced and have a full 4 wheel alignment check carried out.  Once the wheel alignment ( I would recommend new tyres on the rear when this is done, as this would eliminate the tyres as a source of the noise. If they are the noise generators just carrying out the wheel alignment will mot stop the noise).

 

Once this is done then you will be able to start chasing a wheel bearing noise if it still exists.  

 

Rear noise is quite common from the Octavia - the tyres are usually the culprit not wheel bearings.

 

Hope this helps.

[nickguzzi]

Swapping wheels rear to front may give you some idea, rather than buying anything at this stage.

 

Take care. The car can feel a bit "strange" for a while until the tyres have scrubbed into their new profile.

[phillip]

Swapping wheels rear to front may give you some idea, rather than buying anything at this stage.

 

Take care. The car can feel a bit "strange" for a while until the tyres have scrubbed into their new profile.

+1 from me on this...I swapped mine over a few weeks ago, and I now have a rumbling noise when slowing down, but I know it is just down to the tyres.

[richardsfavorit]

Thank you all for your responses. Most helpful.

It sounds like simply swapping the wheels front to back might be a good indication of what could be wrong, plus I should be able to have a look at the tread as I am doing so.

The wobble issue only happens on a smooth surface, would that indicate the saw toothing?

[radders567]

Thank you all for your responses. Most helpful.

It sounds like simply swapping the wheels front to back might be a good indication of what could be wrong, plus I should be able to have a look at the tread as I am doing so.

The wobble issue only happens on a smooth surface, would that indicate the saw toothing?

Just have a good look at the rear tyres before you do anything.  Run your hand around the circumference if the edges of the tyres are slightly raised on the edges of the tyre blocks then this would indicate saw toothing.  As stated this can be cured with a full 4 wheel alignment.  Tyres can be swapped about, however if the rears are worn just save your self the hassle and get new ones. By swapping front to rear it will tell you that it was the tyres (assuming the front tyres are evenly worn and correctly balanced).

[sniper29a]

change the wheel bearing, it cost nothing - what else could make noises? Does wheel rub the chassis? Is your tires unevenly worn? Worn rubber bushes usually create roof like tires wear (at least in my case but it is caused by race style driving)

 

As per wobbles...most likely damaged rubber bushes and everything just moves around instead holding wheel in right place. I destroy ever few kilometres front bushes - changed for Powerflex poly-urethan...never had problem so far and it lasts forever.