Cardone 82-3904A Window Regulator - Front Left

Cardone 82-3904A Window Regulator for Mercedes-Benz

Restore front left window movement with the Cardone 82-3904A window regulator. This new electric regulator is built for 1978-1981 Mercedes-Benz 300D applications with power windows, giving you a direct replacement for worn or failed lift mechanisms.

Cardone’s Window Regulator line focuses on correcting original design weaknesses while keeping the window lift motor working under less strain. The result is a stand-alone regulator solution for the Mercedes-Benz 300D that supports reliable glass travel and consistent operation.

Key Features

• 100% new construction for dependable window lift operation
• Guaranteed fit, form, and function
• Meets or exceeds OEM performance expectations
• Corrects original design flaws for longer service life
• Stand-alone regulator design for a cost-efficient repair
• Front left mounting position for electric window systems
• Includes installation instructions
• Metal and plastic construction

Detailed Description

The Cardone 82-3904A is a new front left window regulator engineered for Mercedes-Benz 300D models from 1978 through 1981 with power windows. It is designed to replace a failed regulator assembly and reduce unnecessary load on the window lift motor, helping the system operate more smoothly. If you are servicing a Mercedes-Benz 300D, 82-3904A provides a direct-fit replacement built around the original application.

This Cardone Window Regulator line is focused on correcting known OE design issues rather than duplicating them. That approach supports long-lasting performance and makes the 82-3904A a practical choice when the window is slow, stuck, or no longer tracks properly. This part cross-references Mercedes-Benz 1237202746 for the same application.

What It Helps Fix

• Window glass that will not raise or lower properly
• Grinding, binding, or uneven window travel
• Excess strain on the window lift motor
• Failure caused by worn regulator components
• Loss of smooth electric window operation in the front left door

Installation Notes

Fits 1978-1981 Mercedes-Benz 300D, front left. Confirm the vehicle has power windows before ordering. The package includes a window lift regulator and instruction sheet; motor and mounting hardware are not included. Verify door configuration and match the original regulator layout before installation.

Quality Assurance

Cardone builds this regulator as a new replacement part with corrected OE design weaknesses and performance targets aligned to OEM expectations. The 82-3904A is intended to deliver reliable operation in the Mercedes-Benz 300D window system while helping reduce premature motor wear.