On this '89 740 turbo sedan, 120,400 miles I believe it has the jumbo brakes (single piston) but I don't know the brand

Had the single, large sliding pin with the pad holder which unbolts and swings upward off the rotor for easy pad replacement (Jeeze, it would have been easier to go look at the calliper for the brand)

Anyhow, when I first back down the driveway, the brakes initiallly grab, then I hear a distintive, loud, click and feel the pedal sag and the car lurch faster out of the driveway.

It is like something which was set by the initial brake pressure has let go and it now take more pedal pressure to achieve what grip it began with.


Any ideas?
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"Can't understand why people abort Volvos, either"