The standard Mercedes routine is to replace rotors with every second set of pads. Don't machine the rotors - you're correct in saying there isn't enough material to do that. Rotors are cheap, so I don't mind replacing them. But kind of a PITA with a W123 because you have to mess with the bearings.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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