i have a ford focus 2001,went out to car and reversed,and there was a clunk from the front end,thought nothing of it, then drove down the hill to t juntion and applied brakes,peddle went to floor and no brakes,luckily there were no cars coming as i quickly pumped the brakes and they came good again,but i was well out on the road by this time and was very lucky,kept trying brakes on flat road and they seem ok,have driven about 10 miles now testing brakes all the time and they are ok
what could have caused this?and could it happen again
I think I would check out the brake system or have it done.
In my experience noise on first movement happens when a car has been stood for several days or overnight in freezing conditions and is caused by the pads/shoes being stuck by rust to the disks/drums or in freezing conditions frozen on. It sounds as though your brake cylinders (that push the pads) had been pushed right in , when you pumped the pedal you forced them back out to their normal position. I cannot think why this should happen in normal use though.
I have noticed that when I wash the brake dust off from the front wheels, that if I don't take the car for a spin round the block, and use the brakes a couple of times, the brakes seize, and make a noise as soon as I start to reverse out onto the road.