If the car "shutters" while braking the problem is usually the front rotors being warped.
The 1992 500E caliper problem was a shrill squealing noise at 10-30 mph when the brakes WEREN'T being used.

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MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
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