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23386455 603-861 Coolant Reservoir Tank with Cap Compatible with 2016-2021 Chevrolet Blazer, Equinox, Malibu | Cadillac XT4, XT5, XT6 | Buick Envision, LaCrosse, Regal Sportback & TourX | GMC, etc

4.5 (3) Write Review
Free shipping on orders over $29.99

$34.31

$ 14 .99 $14.99

In Stock
  • When Should I Replace My Coolant Reservoir Tank? A coolant reservoir is part of the engine cooling system and is a small plastic container attached to the radiator or engine block. Its main function is to collect and store excess coolant that expands when heated, and it plays a very important role in the cooling system. If your car is experiencing problems such as engine overheating, low coolant levels, leaks, and coolant odor, you may need to replace your coolant reservoir.
  • Replacement Part Numbers: 603-861, 603861, 23386455. Please check the detailed description or enter Year/Make/Model to check your compatibility before purchasing this radiator overflow tank.
  • Compatible with Select Buick, Cadillac, Chevy & GMC Models: 2021 Buick Envision, 2017 - 2019 Buick LaCrosse, 2018 - 2020 Buick Regal Sportback, 2018 - 2020 Buick Regal TourX, 2019 - 2021 Cadillac XT4, 2017 - 2021 Cadillac XT5, 2020 - 2021 Cadillac XT6, 2020 - 2021 Chevrolet Blazer, 2018 - 2021 Chevrolet Equinox, 2016 - 2021 Chevrolet Malibu, 2017 - 2021 GMC Acadia, 2018 - 2021 GMC Terrain.
  • Direct Replacement - Perfect match, direct replacement. When replacing the coolant overflow tank, please turn off the car and wait for the tank to cool down before proceeding. This coolant reservoir replacement is made from premium materials to ensure superior quality and long-lasting performance. This is not a genuine part, but an aftermarket replacement.
  • Service Guarantee - We have strict quality control standards to ensure high performance. If you have any questions or concerns, please feel free to contact us.


Product Description

603-861 Coolant Reservoir Tank
replacement part number
compatible with
Product Specifications

Product Specifications

  • Material: Quality Plastic
  • Color: White
  • Cap Included: Yes
  • Cap Type: Spring Loaded Twist
  • Pressurized: Yes
  • Packaging Type: Box
  • Shape: Spherical
  • Package Included：1 x Coolant Radiator Reservoir Tank; 1 x Cap

More Details

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Narje
Reviewed in the United States on March 1, 2025
The part was a great fit
Rey Rivera
Reviewed in the United States on February 18, 2025
Works as advertised
LP
Reviewed in the United States on October 13, 2024
The tank is a great replacement for the OEM on my XT5.The quality / thickness of the plastic is like the original, the cap from the original even fits.If you need the coolant tank, this one is a good buy - much cheaper than OEM and definitely appears to be as good or better than the original.
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