Vibration/humming from the rear

[rob893]

I have a 03 172 cup, over the past few weeks I have noticed a vibration/humming sound from the rear that is getting gradually worse.

It first started making the noise at 27mph precisely, then it was at 27 mph and 45-47 mph, now it is happening almost all the time.

The noise itself is a vibration humming like noise. Its not a constant noise though, its more like a tapping noise, but instead of a knock its a hum. At 50mph its about 8 times a seconds, 30mph its half that. Quite hard to explain. I have tried to get a video but my phone's Mic sucks. Its not effected by engine revs, the gear Im in or any bumps or suspension travel. It is only effected by the speed Im travelling, the faster I go, the quicker the noise. It almost sounds like something that spins is a bit loose and is causing the noise. Unfortunately my mechanical knowledge is limited so I have no idea what's going on.

My car had an Mot and service at ktec last month so Im not sure what's going on as it passed with flying colours.

Any ideas?

Thanks

 

[levaz]

wheel bearing

 

[rob893]

Thanks for the quick reply.

I will do some investigating. How much should this cost at a reputable garage?

 

[Tony Hunter]

New set of rear discs either from Renault, or G172 on here. 40mins to do both sides done.

 

[rob893]

The rear discs were replaced January 2011, surely they won't need to be replaced so soon again?

 

[Jekyll]

Thanks for the quick reply.

I will do some investigating. How much should this cost at a reputable garage?

I took mine to dan at 519 and it was around £90 fitted that included parts and labour. I had a sticky rear caliper and front wing to be fitted and it all came to just over £150 all fitted and fixed.

 

[ben lee]

The rear discs were replaced January 2011, surely they won't need to be replaced so soon again?

the wheel bearing is part of the discs.

 

[Tony Hunter]

The rear discs were replaced January 2011, surely they won't need to be replaced so soon again?

Were they genuine ones or gsf/euro parts ones?

 

[Dan519]

The rear discs were replaced January 2011, surely they won't need to be replaced so soon again?

probably if you didn't buy genuine.