Mercedes W221 Rear Door Window Interior Seal Rubber Gasket Left N/S A2217351165

The Mercedes W221 Rear Left Door Inner Window Seal is an original part from the Window Seals and Trim group, designed for installation on the rear left side. It ensures a tight seal for the window, reduces wind noise, and supports the proper operation of the window regulator in luxury S-Class sedans.

Specifications and technical data

• SKU: A2217351165
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2217351165
• Substitutable numbers: A2217351165, A 221 735 11 65
• Location on the vehicle: Rear, Left
• Part type: Inner Beltline Seal
• Category: Window Seals, Gaskets & Trims

Purpose and Function in the Mercedes W221 Body

The presented seal is dedicated to the rear left door area of the Mercedes S-Class W221 model. As an internal component, it guides the window within the door frame, stabilizes its movement, and creates a barrier between the glass and the door panel.

In practice, this means:

• reduction of window vibrations and play during driving,
• prevention of water and dirt ingress into the door interior,
• reduction of cabin noise at higher speeds,
• protection of the window edges against excessive wear.

Benefits of Using an Original Seal

The original rear left door inner window seal is designed specifically for the geometry of the Mercedes W221 door, ensuring precise fit to the frame and window. The correct rubber profile and optimized stiffness support smooth operation of the window regulator and reduce the risk of jamming.

Key advantages include:

• Structural Compatibility – maintaining factory assembly tolerances and the correct window line relative to the seal.
• Stable glass guidance – reduced load on the window regulator mechanism, contributing to its durability.
• Improved acoustic comfort – reduction of noise in the rear cabin, important in premium vehicles.

Material and Operational Characteristics

The seal belongs to the group of rubber and flexible elements that operate in variable temperature conditions and with frequent window movement. The manufacturer's design considers:

• resistance to typical operational loads in rear doors,
• retention of flexibility across a wide temperature range,
• ability to withstand multiple window opening and closing cycles without losing its guiding function.

The part comes from a used vehicle, which means it is a component with parameters consistent with factory specifications, intended for further use after proper installation.

Installation in the Rear Left Area

The seal is designed for installation in the rear left part of the body, within the passenger door. When replacing, it is recommended to:

• check the condition of the window guides and the regulator mechanism,
• clean the channels where the seal operates of sand and dirt,
• verify the window's fit along its entire length after installation.

A correctly installed seal helps restore the window's factory operating parameters, which is particularly important in S-Class vehicles where high acoustic comfort and sealing are expected.

Complementary Parts and Technical Advice

If you are planning a comprehensive repair or upgrade of the window area in your Mercedes and need other parts from the same group, such as inner window seals, outer window trim, or additional sealing profiles, check the available parts in the Mercedes Window Seals and Trim category.

For users who are simultaneously servicing the vehicle's thermal comfort systems, a guide on selecting and operating air conditioning and heating components may be helpful – detailed tips can be found in the article Air Conditioning and Heating – Part Selection and Maintenance for Year-Round Comfort.

Summary

The Mercedes W221 Rear Left Door Inner Window Seal is a functional body component that affects acoustic comfort, protects the window mechanism, and contributes to the aesthetic operation of the window. Choosing an original component from the Window Seals and Trim group helps maintain the structural integrity of the door and reduces the risk of future window guidance problems.