Awful screeching noise when up to temp

[Bill Hill]

Hi, I've a 2010 Insignia sport touring 170 with 130k on the clock. Recently its been making a terrible noise after about 15-20 minutes of running- so when everything is up to temp. I can't pin down even if it's front/back as the sound is so loud. To describe it- very high-pitched metallic sound, like metal on metal. It goes away when stopped and when braking. It definitely sounds like its at a corner rather than engine-bay (not belt(s)/gearbox/wheel bearing). I've had a mechanic replace sticking calipers, pads, missing guides/slides for pads, swapped out a disk from another insignia but the noise is still there. Also- put the front up in the air and ran it in gear while applying brake on/off. Front eventually stopped turning freely, couldn't turn by hand. Replaced flexi hose and wheel turning free again when hot but noise is STILL there. Anyone got other suggestions? Other than new mechanic... i'm already looking for another! Cheers

[Vauxhall Owners Club]

Hi Bill.....welcome to the Forum

If it is coming from a rotating wheel then it has to be either pads or discs rubbing.
Alternatively, a driveshaft/wheel bearing issue but if it was me I would simulate the problem by clamping off the brake hoses (individually) and running the car with the pads separated slightly away from the disc and listen for noise when applying the brake (when moving very slowly)

[Bill Hill]

Thanks Admin. It's for a new mechanic tomorrow, when (not if) it finally gets sorted i'll post back here what was done to fix

[Vauxhall Owners Club]

Cheers and fingers crossed!

 

[H3X4L]

Hello Bill,

I think I have the same problem as you had.
What was the issue then?

[Burt]

I've got a 2011 CDTI. Tracked the squeal to the nearside rear wheel. 

I knew it wasn't wheel bearing or pad related because it was the same pitch regardless of wheel speed.  And intermittent.

I removed the brake pad carrier and shook it violently.  There was the sound.  Basically ( in my case ) the handbrake cable has a ball on the end that sits in a small bracket on the back of the Carrier.  The ball is getting on a bit and showing signs of weathering along with the bracket,  showing rust lines down the bracket. I greased the ball where it sits in the bracket ( because I had the car on axle stands with the handbrake off the ball had freedom to move slightly in its enclosure allowing enough space to let the grease get at it.  

Problem solved. 

I'll be honest,  it'll probably be back again soon when the grease wears off but I reckon I'll just replace the handbrake cable and grease the new one on install.  

Some of you may have the same issue  hope this helps.