Audi A8/S8 Coolant Reservoir / Tank / Bottle 4H0121403H

OEM Part #: 4H0-121-403-H (4H0121403H)

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Other Coolant Reservoir / Tank that may fit your vehicle

Coolant Reservoir / Tank / Bottle Cap 3C0121321

Coolant Reservoir / Tank / Bottle Cap

$14.99
Fits 2006–2024 Audi, Porsche + more
OEM: 3C0121321
Used
  • Genuine OEM — real photos
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  • Ships from our own indoor warehouse

This genuine Audi coolant reservoir, also known as an expansion tank, features OEM part number 4H0121403H and is designed specifically for 2013-2018 Audi A8 and S8 models with 4.0L and 6.3L engines. Located in the engine bay, this part plays a critical role in maintaining optimal coolant levels and temperature within your vehicle’s cooling system. If you’re experiencing overheating issues or coolant leaks, a worn-out or damaged reservoir may be the culprit. This factory-original part ensures reliable performance and compatibility, helping to prevent further engine damage. Other compatible part numbers include 4H0121403N and 5Q0121321, among others. Choose this authentic piece for a seamless fit and function.

Specifications

Specifications for Coolant Reservoir / Tank / Bottle 4H0121403H
Fits Vehicle ModelA8, S8
Fits Vehicle MakeAudi
OEM Part No4H0-121-403-H (4H0121403H)
CategoryRadiator / Coolant

Compatible Vehicles

Fits 20 vehicle configurations across 1 make, 2012-2018.

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.

Audi

  • A8 2012-2018 · 14 variants 11 with notes
  • S8 2013-2018 · 6 variants 6 with notes
View all 20 vehicle configurations — 17 with fitment notes
Full vehicle fitment list for Coolant Reservoir / Tank / Bottle 4H0121403H
Year Make Model Trim Engine Note
2012 Audi A8 Quattro L Sedan 6.3L W12
2013 Audi A8 Quattro Sedan 4.0L V8 Turbo For Vehicles with Production Date After 06/23/10; For Vehicles with Engine Code(s) CEUA, CGTA
2013 Audi A8 Quattro L Sedan 4.0L V8 Turbo For Vehicles with Production Date After 06/23/10; For Vehicles with Engine Code(s) CEUA, CGTA
2013 Audi A8 Quattro L Sedan 6.3L W12
2013 Audi S8 Sedan 4.0L V8 Turbo For Vehicles with Production Date After 06/23/10; For Vehicles with Engine Code(s) CEUA, CGTA
2014 Audi A8 Quattro Sedan 4.0L V8 Turbo For Vehicles with Production Date After 06/23/10; For Vehicles with Engine Code(s) CEUA, CGTA
2014 Audi A8 Quattro L Sedan 4.0L V8 Turbo For Vehicles with Production Date After 06/23/10; For Vehicles with Engine Code(s) CEUA, CGTA
2014 Audi A8 Quattro L Sedan 6.3L W12
2014 Audi S8 Sedan 4.0L V8 Turbo For Vehicles with Production Date After 06/23/10; For Vehicles with Engine Code(s) CEUA, CGTA
2015 Audi A8 Quattro Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2015 Audi A8 Quattro L Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2015 Audi A8 Quattro L Sedan 6.3L W12 For Vehicles With Production date Up To 10/16/17
2015 Audi S8 Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2016 Audi A8 Quattro L Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2016 Audi A8 Quattro L Sedan 6.3L W12 For Vehicles With Production date Up To 10/16/17
2016 Audi S8 Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2017 Audi A8 Quattro L Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2017 Audi S8 Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2018 Audi A8 Quattro L Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17
2018 Audi S8 Sedan 4.0L V8 Turbo For Vehicles With Production date Up To 10/16/17

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