I drove 15 mi to work, via high way, with e brake partially on. When I got there, the wheel was smoking. I pour gallons of water on them and let it cool down and drove again for about 10 mi. Now I found the brake didn't seems to returned after it's applied, the rear wheels would be almost fully locked after no more than 10 times of braking. The more the brake is applied, the the shallower the pedal gets. So I towed the car back home. What could the heat do to have caused my rear brake to stuck whenever it's applied? It seems to returned after an hour wait. I imagine the heat must have melted (or distorted the shape of) anything that made of rubber, like brake hose(the fluid becomes reluctant to flow in and out of the piston?), seal, etc. However, I only know how it generally works and is generally designed. It's W123, an 84 Mercedes 300 D. I should have taken a look at it b4 I post this message, but I thought the earlier I post the better because I'll have to have it work in 2 days(back to work doing pizza delivery). Any thought would be appreciated. Grasius (^_^)