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Engine Coolant Expansion Reservoir Overflow Tank 603-638 Compatible with Audi A4 Audi A4 Quattro 2002-2009 Replace 8E0121403 376737131 8E0121403 FRT1108C FRT1108C 603638 Coolant Reservoir Tank

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$28.49

$ 12 .99 $12.99

In Stock
  • 【Vehicle Fitment】Coolant overflow tank fit for 2005-2009 Audi A4 2.0L l4, 2005-2009 Audi A4 Quattro 2.0L l4, 2005-2009 Audi A4 Quattro 3.2L V6, 2006-2008 Audi A4 3.2L V6, 2002-2006 Audi A4 1.8L l4, 2002-2005 Audi A4 Quattro 1.8L l4. You can check your vehicle's suitability in the Amazon Suitability Filter in the upper left corner. For more information, please check the pictures or the item detail page.
  • 【OE Standard】603-638 Coolant expansion tank Replaceable Part OE No.: 603638, Z49037, 8E0121403, 376737131, ‎APET0134, DAKG-21403M, FRT1108C, SK603638, 8E0121403, 603-638 coolant tank. Our reservoir tank meet or exceed OE standards for form,fit and function,Ideal for automotive replacement engine coolant recovery kits. 100% brand new and high quality auto parts with OE grade durability for the ultimate comfortable driving experience.
  • 【Material & Function】The overflow tank reservoir is made of safe, high-quality PP plastic material, which can withstand excessive heat and vibration, and its function is to store excess coolant when needed, which helps to reduce oil dilution, fuel consumption, cylinder bore wear, and tailpipe emissions, and improves the efficiency of the heating system. The level of antifreeze inside can be seen directly without opening the radiator cap, avoiding damage to car parts.
  • 【How it works】 Automobile expansion tank is commonly known as the antifreeze reservoir tank, water reservoir tank, is an important part of the cooling system. It contains coolant discharged from the engine cooling system. When the coolant is at a high temperature and expands through the radiator, or there is an excess of coolant, pressure builds up and is released. After the engine cools, the excess fluid flows from the vehicle's coolant tank back to the radiator.
  • 【After-Sales service】 SYKRSS This well-crafted coolant tank reservoir comes with a 12-month warranty and top-notch customer service. If you have any questions about this coolant reservoir, please feel free to contact us and we will get back to you within 48 hours.


Product Description

603-638 Coolant Reservoir
603-638 Coolant Reservoir
Coolant Reservoir
For Audi 2002-2005 Audi A4 Quattro 1.8L l4
For Audi 2005-2009 Audi A4 Quattro 2.0L l4
For Audi 2005-2009 Audi A4 Quattro 3.2L V6
For Audi 2002-2006 Audi A4 1.8L l4
For Audi 2005-2009 Audi A4 2.0L l4
For Audi 2006-2008 Audi A4 3.2L V6
Coolant Overflow Tanknsion Reservoir Overflow Tank

AJS74
Reviewed in the United States on March 20, 2025
Very good quality part for the price, very satisfied customer here! (17 year veteran certified expert Audi technician )
Sam serrano
Reviewed in the United States on November 9, 2024
Yes exactly the same part easy swap no problem
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