Brake noise on full lock

[ecurie]

I own a 1979 Rolls Royce Silver Shadow which has developped folowing problem :

with the steering on full lock (left or right) and then braking (even lightly), there is a loud, grinding noise coming from the front.
The moment I release the brakes or when straightening the steering, the noise stops immediately.

I removed the front brake pads to check for abnormal wear, but they look fine.
When reinstaling them, I coated the back with fesh copper grease, but the noise is stiill there.

Any ideas what could be the cause ?

[harvey]

Suspension bushes worn allowing the tyre to rub on something.

[ecurie]

Suspension bushes worn allowing the tyre to rub on something.

Maybe, but it sounds more like metal on metal and only occurs when braking.

[suffolkpete]

Wheel bearings worn allowing the discs to touch the calipers or backplate? Do R-R bearings wear?

[harvey]

Do R-R bearings wear?

Everything wears on those things....

[ecurie]

Wheel bearings worn allowing the discs to touch the calipers or backplate? Do R-R bearings wear?

Unfortunately, R-R pars wear just as quickly as on other cars

The bearings seem to be OK, with no play or strange noises. Also, it would till not explain why it only happens when braking at low speed.

[JPB]

Well it would if the tracking had been set so that a front wheel was scrubbing, even slightly, on lock. That would allow the disc to catch on the caliper frame and wouldn't necessarily require a massive amount of runout given the diameter of these discs. Unless you have a small bit of gravel stuck behind the dust shield and even then, only some extra bearing play would explain the fact that this noise happens only when on lock.

Have you had the car up in the air for a better look or does it not do it unless the weight is on the wheels?

[ecurie]

That is an interesting remark : I had the tracking on the car done a few months ago and, while I'm not entirely sure, the grinding noise started more or less in that period.

I will check with the front wheels of the ground and also check for rubbing marks.