The gear on the starter usually looks fine when the bendix drive is faulty. The gear, as you know, slides on the drive to engage then spin in away from the ring gear. Depending on the starter age, replacing just the bendix might be not the way to go. Every time I replace a starter, I put wheel bearing grease on the gear and the shaft to coat the shaft but to also make the starter a little quieter in operation. Not required, but I've had good luck by doing it.

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81 300CD (sold) 1972 280 SEL 4.5 (sold) 1966 250 S 4 spd (sold) 1974 450 SL (sold) 86 BMW 325ES (sold), 1973 280C (sold) 1988 300 SE.