In most cases this is both the motor and the regulator. When the regulator starts to wear, it will cause resistance and then the motor has to work harder. Replace both and the problem is solved.
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Benzmac:
Donnie Drummonds
1992 500E (very soon I hope

1981 280GE SWB
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
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