I keep getting a clunking sound when braking that seems to come from the rear brakes. I've got a 01 caravan with rear drums. The last time this occurred my mechanic machined the drums and manually adjusted the rear brakes. He mentioned that the drums were out of round- though he had machined them less than 10K before. I have now put another 7K on the van and the rear brakes are making that familiar sound once again. What gives? Do we have to manually adjust the rear brakes every 10K? How can I tell if the rear adjusters are not working properly? Previously I had a pulsating pedal when braking that I thought was linked to warped rotors, though the pulsation decreased when the rear brakes were adjusted. Anyone have similar problems?