When braking the other evening I detected the unmistakeable sound and feel of metal on metal, which surprised me, because I'd replaced front pads and rear shoes less than a year ago.
On investigating the next morning I found the LH pair of front disc pads evenly worn, with about 7mm of pad thickness remaining. On the RH side one of the pads was still about 10mm thick. The other was down to metal.
I'll be keeping a close eye on the new pads, but I'm a bit baffled as to the cause of the asymmetric wear. The Girling caliper is free to move laterally on a pair of guide pins moving in the fixed carrier frame. A single piston acts directly on one pad and the free movement of the caliper allows an equivalent load to be applied to the other pad.
When I removed the RH caliper, the guide pins did not seem to be seized or stiff, although the rubber boot on one had come adrift at one end and there was some minor corrosion on the pin, which I cleaned up and re-greased. But if one or both of the pins had seized, so that the caliper could not move laterally, I would have expected the excessive wear to occur on the pad under the piston. In fact it was the other pad which had worn down.
Does anyone have an idea as to how the pad on the non-piston side could experience such excessive wear?
Peter Brumby