Interesting, I guess they don't do different length linings anymore. In high school auto shop I was told that they're different lengths because the softer, shorter front lining primarily functions to push the larger, harder rear lining harder into the drum, and that's where the braking effectiveness/boost comes from, and why the name 'Duo-Servo.' Versus the old huck brakes that didn't use drum rotation to their advantage, just rammed the shoes out with wheel cylinder pressure.
