Porsche 911 Cabrio 996 Quarter Window Inner Seal Rear Left N/S 99654347900

Porsche 911 Cabrio 996 Quarter Window Inner Seal Rear Left N/S is an original body component from the Window seals and trims group, designed for installation in the rear left part of the cabin. It ensures a tight fit for the side window, reduces wind noise, and helps maintain proper protection of the interior against water and contaminants. This is a practical solution for owners of the Porsche 911 Cabrio 996 generation who want to restore the correct operation of the window mechanism and maintain factory driving comfort.

Specifications and technical data

• SKU: 99654347900
• Mark: Porsche
• Condition: Used
• OEM Part Number: 99654347900
• Substitutable numbers: 99654347900, 996 543 479 00, 996 543 177 01, 996 54 3 1 77
• Location on the vehicle: Rear, Left
• Part type: Inner Beltline Seal
• Category: Window Seals, Gaskets & Trims

Purpose and function of the seal

The presented seal has been designed specifically for the rear left side window in the convertible body style. Its tasks include:

• stable window guidance in the frame and reduction of operating play,
• sealing the contact point between the glass and the bodywork,
• reduction of wind noise at higher speeds,
• protection of the interior against water, dust, and fine contaminants. Thanks to its proper profile and fitment to the specific body model, the seal works with the window lifting mechanism without hindering its operation or causing excessive resistance.

Construction and fitment for Porsche 911 Cabrio 996

The seal is a structural component dedicated to the convertible body, where the side line and window frame geometry differ from the coupe version. Its properly contoured shape allows for:

• precise adhesion to the window edge and body components,
• maintaining the continuity of the sealing line in the rear part of the vehicle,
• reduction of stress at contact points during the operation of the folding roof. Proper fitment to the specific location on the vehicle (rear, left side) minimizes the risk of leaks, which often occur when using universal profile replacements.

Condition of the component and service application

The offered seal is a used component, which makes it an attractive option for maintenance and restoration repairs. This type of part is particularly useful in situations where:

• the original seal is perished, cracked, or deformed,
• there are water leaks in the rear part of the cabin,
• excessive noise appears in the area of the rear side window,
• replacement of the component is necessary after bodywork and paint repairs. Choosing an original, used part allows you to maintain the structural integrity of the body and avoid problems with improper fitment, typical of low-quality replacements.

Benefits of installation and service tips

Installing a properly selected rear side window seal brings measurable utility benefits:

• improvement of acoustic comfort inside the vehicle,
• reduction of the risk of bodywork corrosion in the rear window zone,
• maintaining the aesthetics and tightness characteristic of the Porsche brand,
• stable window operation during frequent opening and closing. When replacing, it is worth paying attention to the condition of the guides, mounts, and window position adjustment to fully utilize the potential of the newly installed seal and avoid future leaks.

Complementary components and car project development

If you are planning a broader renovation of the window and roof area in your Porsche, a good step might be to review other items from the Window seals and trims group to restore the consistency of the entire sealing system during a single service intervention. In the case of interior modernization or improving ergonomics, it is also worth considering replacing seats with branded components from dismantling – you can find more on this topic in the article on the impact of branded used seats on comfort and car value. If you are simultaneously working on the engine fuel system and looking for savings on parts from dismantling, the guide on how to safely choose a used injection pump and fuel rail may be helpful, which suggests what to look for when purchasing used components.