General Noise - not wheel bearing

[zed]

Ok, GP 16V 1.4 65K miles.

Got a rotational noise from the front left. Gets worse as the car gets faster - appears to be related to wheel speed and not Engine speed.
I.e. doesn't matter what gear you're in or whether you're in or neutral - depress clutch.

At 60 mph - you can hear the rotational noise above the radio.

Had two attempts at the wheel bearing and has had no effect.

Garage can't identify where the noise comes from, so what to do next is a bit iffy and potential expensive.

Other bit of info is the front left went into a small collapsed drain on road works on the motorway, and it bent the alloy, 2 years ago, but never got the wheel changed for about 5 months as wasn't noticeable unless at high speed.

Any ideas?
Thanks in antic. Z

 

[Reuuk]

go to another garage.

check the CV joint they make a 'rotary/banging' noise

could even be a loose wheel!

 

[zed]

Indeed - maybe gonna try the independent guy in East Kilbride - been mentioned on here a number of times.
Things that have been mentioned are the Hub Carrier and Final Drive.

I appreciate it's not easy, as it sounds just like a knackered bearing (if you've had a GP you recognise the noise)

Almost feel like it needs a run on a rolling road and a sound sensor to see where the noise is.

 

[Skyperr]

Firstly, and just to be safe, eliminate the tyre and wheel by swapping it around with one of the rears.

Secondly I've seen a similar being caused by a bent hub. Remove the brake disk and run the car in gear on an axle stand and watch for eccentricity. Those hubs are soft and easily bent if the front is kerbed. Whoever replaced the bearing may not have picked up on this and pressed the defective hub back in - assuming it was properly pressed!

Another potential cause is if the lock nut on the driveshaft is over-torqued. They are only supposed to be tightened to 70Nm + 55 degrees. Most fronts and rears using a similar set up are torqued to around 3 times that.

I would imagine final drive will cause the a noise if either wheel front is spun when run in gear when raised. I doubt if this is your problem

 

[Peter Pick-Up]

Cupped tires ( sawtooth profile) makes EXACTLY the same noise as worn bearings....
It got me fooled last winter on my Alfa GT, I was sure one or both of the front bearings were gone, after replacing them, the noise was still there.
When I changed for summer tires, the noise was gone...!

 

[zed]

Thanks for the replies.

Don't think it's the tyres as the wheels have been rotated - I got my alloys reconditioned about 5 months back (Skidz in Falkirk - thoroughly recommended), so they've been off and on - and had the noise for a long time before then
There's always been a lot of road noise from new due to the tyre size - should say the car is unmodified - no lowering etc.

Have now got quite used to bearing noise and replacements as we have two GPs with 149K miles between them - this is worse and getting worse.

I'm probably going to go for second opinion(s).

 

[Skyperr]

Good point about the tyres.I have Vredestein Sportracs that have this sort of thread profile and these make a slight but noticeable bearing-like howl at low speed. The thread profile looks something like a cup. Great driving tyre but a pain in the ass with the noise.

 

[Peter Pick-Up]

V-type pattern/profile is well known for being noisy...

Cupped tires or sawtooth profile is something different, it only occurs on the outside part of the tire, and mainly on the rear axle...
But when driving the car, it is almost impossible to tell where the noise is coming from, front or rear, left or right...

 

[Skyperr]

V-type pattern/profile is well known for being noisy...

Cupped tires or sawtooth profile is something different, it only occurs on the outside part of the tire, and mainly on the rear axle...
But when driving the car, it is almost impossible to tell where the noise is coming from, front or rear, left or right...

Couldn't agree more with the last sentence..

 

[zed]

From memory (it's chucking it outside), my tyres are all Bridgestone BT50 Potenza 205/45W/17. Reasonably certain it's not the tyres.
The noise gets really bad over 60.