When parking brake starts dragging, the shoes get progressively hotter and expand more than the drum (because it's built into the rotor - so it doesn't expand much), to the point where the drum glows and smoke pours from the affected wheel. The shoes can be repositioned and after they cool (shoes shrink), the problem (drag) decreases to minimal until the next occurrence. All other drum brakes I have encountered are designed to remain vertically centered (can't drop) so they don't drop out of position and drag on, or bind with, the drum. This is an incredibly stupid design flaw especially on a 4x4 truck.
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When parking brake starts dragging, the shoes get progressively hotter and expand more than the drum (because it's built into the rotor - so it doesn't expand much), to the point where the drum glows and smoke pours from the affected wheel. The shoes can be repositioned and after they cool (shoes shrink), the problem (drag) decreases to minimal until the next occurrence. All other drum brakes I have encountered are designed to remain vertically centered (can't drop) so they don't drop out of position and drag on, or bind with, the drum. This is an incredibly stupid design flaw especially on a 4x4 truck.
- caddgeek, Surrey, BC, Canada