Front suspension noise....
 

My old heap is kindly making an interesting noise from the front end - I think it's the left hand suspension, especially under heavy braking. Best described as a graunching sound.... It's not rotational - more of a metal to metal contact?

Brake pads are fine (plenty of meat on them), caliper bolts are fine, and I think the damper bushes are ok too. Certainly no free play / movement in the latter.

What are my likely culprits? I'm thinking top wishbone bushes, caused by the braking drag on the wheel taking up slack in a knackered bush, in particular as the nose dives under braking? Is that logical?

Thanks :)

Very easy to check: (And yes, you're most likely on the right track)

Jack up the left hand wheel, by lifting it under the shock-mount - jack up wheel 'till it's free off ground - this way, you'll release all weight on the upper A-frame - and now it's easy to check for play in bushes etc.

If it is wishbone bushes tehy will have had to worn all teh way through to make a grinding noise. Do check them but you may well need a big bar to pull enough onthem to see movment. Also check the crossmeber where the bottom wishbone bolt goes through. If that moves the crossmember is shot.

Or something easy like the brake backing plate having a crack, and moving into something under different G forces.

Thanks chaps - will take a look at those tomorrow. However after my drive to work this morning, I'm starting to have doubts about it not being rotational, as the noise is not a clonk or rattle.

Is this a very short (time) graunch or does it continue for a while? Does it go away when it's wet?

I'd add the main anti roll bar bushes to the check list.

Don't know about in the wet. It's not a short noise (i.e. like an impact of some kind) - lasts maybe a second or so.

Paul,

Play in front wheel bearing - the sound is from the disk adjusting itself when brakes are aplied.. Or you do have something wrong with brake pads - some play or lose pad..

Don't gamble to much on the way home from work..

Now that makes a lot of sense. The front wheel bearings were all new at the beginning of August, and unusually for me, I haven't used the car much since then. There's no rumbling / roughness when spinning the wheel, so if it's the bearings, presumably it's just the torque figure on the centre nut(s) that needs checking & tightening as appropriate?

Sounds right, yes.. And as I sad in first answer - jack it up as described - this way you'll have no weight (other than wheel itself) on the system - and therefore easy to spot even tiny play's/faults etc. (Don't caunt on a simple spin of the wheel - it could be, that only under 'heavy' load/braking that the micro-play reveals itself).

Volvo Service Manual on Part 6 Front end, has all details of torque etc. you need.