The W123 has what is called fully floating calipers, the W124 has semi floating. The semi is much cheaper to manufacture and lighter. I think the AMG models still have full floating. The change to semi in the W124 is an example of the been counters taking over at MB. The surface of the piston that is exposed is best cleaned if you can, before retracting it. The braking system is much simpler than the fuel system. The ABS system is a different story.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving