The warpage on Wendy's is so slight that I have yet to replace it and it seems the BA is more prone to the problem than the SM. I think it has to do with the difference in amount of breaking force needed per pad on the single disc vs. the dual disc. With the dual disk less force is needed on each pad to attain the same stopping power so it generates less heat. I wouldn't just replace one preemptively since it doesn't happen to all of them.

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