2004-2006 Volkswagen Coolant Reservoir / Tank / Bottle Cap 3D0121321B

OEM Part #: 3D0-121-321-B (3D0121321B)

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This OEM coolant reservoir cap (Part Number: 3D0121321B) is specifically designed for the 2004-2006 Volkswagen Phaeton equipped with the 4.2L V8 or 6.0L W12 engines. As a crucial component located atop the coolant reservoir tank, this factory-original part ensures a secure seal to maintain proper coolant levels and prevent leaks. Incompatible or worn caps can lead to overheating and coolant loss, resulting in engine damage. With its reliable design, this cap restores functionality and optimizes performance of your vehicle's cooling system. Alternative names include "cover," and it can also be identified by compatible part numbers such as 3D0121321 and 3D0121407H.

Specifications

Specifications for Coolant Reservoir / Tank / Bottle Cap 3D0121321B
Fits Vehicle ModelPhaeton
Fits Vehicle MakeVolkswagen
OEM Part No3D0-121-321-B (3D0121321B)
Compatible OEM Part No 3D0-121-321
CategoryRadiator / Coolant

Compatible Vehicles

Fits 6 vehicle configurations across 1 make, 2004-2006.

Check your specific vehicle before ordering. This list shows year, make, and model. Some years have multiple trims or engines that use different parts, and individual listings may have additional fitment notes (e.g. “with sunroof only”). Review the full variant list below, or message us with your VIN and we’ll confirm the match.

Volkswagen

View all 6 vehicle configurations
Full vehicle fitment list for Coolant Reservoir / Tank / Bottle Cap 3D0121321B
Year Make Model Trim Engine Note
2004 Volkswagen Phaeton Sedan 4.2L V8
2004 Volkswagen Phaeton Sedan 6.0L W12
2005 Volkswagen Phaeton Sedan 4.2L V8
2005 Volkswagen Phaeton Sedan 6.0L W12
2006 Volkswagen Phaeton Sedan 4.2L V8
2006 Volkswagen Phaeton Sedan 6.0L W12

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