Rear 1/4 window seal (inner). Porsche 356 COUPE  ❭  64454390

Rear 1/4 window seal (inner). Seal is applied to the body where window opens.
The quarter window seal act as weather seals and vibration buffers for the rear side (quarter) windows. They prevent water, wind, and dust ingress around the moving glass edges while the vehicle is in motion and provide a secure, low-noise interface between the window glass and the body. Proper sealing also supports climate control efficiency and reduces road noise entering the cabin. 

Fits:
Porsche 356 / 356A 1950 - 1959 COUPE
Porsche 356B / 356C 1960 - 1963 COUPE

Diagram ref no 15

• Application: Quarter window (side glass) seal on the left side (OE ref no 64454390300) and right side (OE ref no 64454390400) of the body. Designed to match original Porsche OEM specifications for correct fit and sealing performance.

Installed along the rear quarter window frame on each side of the coupe, these seals ensure the glass sits snugly against the body without gaps or excessive play. They help maintain the structural integrity of the window assembly and contribute to a quiet, sealed interior environment. 

Original quarter window seals can harden, shrink, crack, or detach due to age, heat cycles, and exposure to environmental elements. When they fail:
•  Water can seep into the cabin, leading to damp carpets and interior damage.
•  Wind noise and buffeting can increase, especially at highway speeds.
•  Road dust and exhaust fumes may enter the passenger compartment.
Replacing worn seals restores proper weather sealing, preserves original fit and finish, and helps protect the interior and bodywork of your classic Porsche.

Replace the quarter window seals if you notice:
• Water dripping into the cabin near the rear side windows
• Excessive wind or road noise at speed
• Visible cracks, shrinkage, or gaps in the existing seals
• Loose or detached sealing bead along the window edge
• During a full weatherseal or body restoration project


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