GDUKOP Engine Coolant Overflow Reservoir Tank 603-955 Direct-Fit Kit with Cap & Hoses

The GDUKOP 603-955 engine coolant overflow reservoir tank is a direct-fit replacement reservoir and cap assembly that stores excess coolant to help maintain proper coolant levels and steady engine temperatures.

This replacement tank is engineered to restore the cooling system function on compatible Buick and Chevrolet small SUVs and crossovers. Built from high-temperature polypropylene and supplied as a complete kit with hoses, the GDUKOP 603-955 tank matches OE fitment and mounting points so you can replace a cracked, leaking, or missing reservoir without modification.

Will this reservoir fit my vehicle?

Check vehicle years and engine displacement against the listed fitment before purchasing. The GDUKOP 603-955 is designed to fit a range of 2013–2021 Buick Encore and Chevrolet Trax/Tracker models with specific L4 engines, matching original mounting and inlet/outlet positions.

• Compatible models: 2013–2021 Buick Encore L4 1.4L
• Compatible Chevy: 2013–2014 Tracker L4 1.8L; 2015 Tracker L4 1.4L
• Also fits Trax: 2013–2019 Trax L4 1.8L; 2013–2021 Trax L4 1.4L
• OE numbers matched: 603-955, 603955, 95269001, 95201979, 95380033

What’s included and how easy is installation?

The GDUKOP kit arrives complete with the coolant reservoir tank, an air bleed hose, and a premium molded heater hose for a straightforward replacement. It’s intended as a direct-swap component so installation is typically a quick repair that requires basic hand tools and common shop procedures.

• Included: reservoir tank, coolant reservoir air bleed hose, molded heater hose
• Direct-fit design: no cutting or adapting required for listed vehicles
• Installation: drain a small amount of coolant, remove old tank, transfer hoses, and secure new tank

How does the construction affect durability and performance?

Manufactured from high-quality polypropylene (PP), the GDUKOP reservoir resists high under-hood temperatures, vibration, and chemical exposure from coolant over time. That durability reduces the chance of premature cracking or deformation compared with inferior plastics.

• Material: heat-resistant PP plastic formulation
• Design tolerances match OEM mounting and hose locations
• Engineered to withstand engine bay heat and coolant chemistries

What should I expect after replacing the reservoir?

With a properly installed replacement reservoir, you should regain a sealed, leak-free expansion system and consistent coolant level feedback for the vehicle’s cooling system. This helps the coolant flow and recovery operate as intended without introducing air pockets or uncontrolled overflow.

• Restores correct coolant expansion and recovery behavior
• Reduces risk of visible leaks and cooling system pressure loss
• Compatible cap and bleed hose help prevent trapped air

Who is this for: The GDUKOP 603-955 reservoir kit is intended for owners, mechanics, and DIY enthusiasts who need a reliable, OE-matching replacement for cracked, leaking, or missing coolant overflow tanks on specified Buick Encore, Chevrolet Trax, and Tracker models. Choose this part when you want a durable PP construction, full kit convenience, and exact OE number compatibility to ensure proper fit and function.