Mercedes W177 Window Seal Door Rear Left N/S Sealing Gasket Strip A1777353301

Mercedes W177 Window Seal Door Rear Left N/S Sealing Gasket Strip is an original body component from the Window seals and trims group, designed for the rear left door area in Mercedes compact class models. The precisely shaped profile ensures proper window guidance, reduces wind noise, and helps maintain the vehicle interior's seal.

Specifications and technical data

• SKU: A1777353301
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A1777353301
• Substitutable numbers: A1777353301, A 177 735 33 01
• Location on the vehicle: Rear, Left
• Category: Window Seals, Gaskets & Trims

Purpose and function of the component

The presented sealing strip operates in the area of the rear left door window, responsible for stable glass guidance and the control of airflow and water within the door frame. Thanks to its fitment to the Mercedes W177 body geometry, the component supports the maintenance of proper window edge rigidity and reduces vibrations during high-speed driving.

A properly selected seal in this area is important for:

• reducing cabin noise originating from the rear window area,
• protection against moisture ingress into the door cavity,
• maintaining the correct operation of the window lifting mechanism,
• aesthetic finishing of the glass edge relative to the door panel.

Benefits of using the original window trim

Using the original trim in a Mercedes W177 allows for maintaining factory-standard fitment and predictable window behavior throughout its entire range of operation. The design, tailored to the specific model, minimizes the risk of leaks, rattling, or improper door closing after installation.

The main advantages of this solution include:

• Factory fitment to the body – the seal profile corresponds to the shape of the rear left door frame, which facilitates installation and reduces the need for additional adjustments.
• Stable window guidance – proper rigidity and geometry support smooth glass movement within the guides.
• Improved acoustic comfort – proper sealing around the window reduces wind noise and minor resonances in the rear part of the cabin.

Installation characteristics

The rear left door window seal strip is designed for installation in the rear left part of the body, in the door frame zone. The component works with the factory window lifting mechanism and original door fittings, which allows for maintaining the structural integrity of the entire assembly.

During replacement, it is recommended to:

• check the condition of the contact surface in the door frame,
• verify the smoothness of window operation after initial seating of the strip,
• press the seal firmly along its entire length to avoid local leaks.

Application in service and body repairs

This type of component is particularly useful for repairs following side collisions, window replacement, or when addressing noise and leak issues in the rear part of the cabin. Replacing a worn or deformed strip with an original component allows for restoring proper window operating conditions and improving the overall comfort of vehicle use.

If you are planning a comprehensive repair or upgrade of the side glazing area in your Mercedes and need other components from the same group, such as additional trims, frame seals, or window edge finishes, check the available parts in the Mercedes Window seals and trims category.

For drivers interested in a broader approach to drivetrain repairs and making an informed choice between used OEM components and replacements, you will find valuable information in the article Humming differential? Find out why a used OEM drive axle is a better investment than an uncertain replacement, which helps in better planning the service strategy for the entire vehicle.