YzusGomumu Mazda 3 Front Coolant Reservoir Tank with Cap — 2004–2013 Fit, PA Plastic Durable Replacement

YzusGomumu front engine coolant reservoir tank with cap is a direct-fit replacement overflow tank designed to restore proper coolant storage and pressure control for Mazda 3 models from 2004–2013.

If your Mazda 3’s original coolant reservoir is cracked, leaking, or discolored, installing this replacement restores the system’s ability to collect and return excess coolant as the engine warms and cools. Built from durable PA (polyamide) plastic, this tank resists heat and corrosion found under the hood and comes with the matching cap for a complete swap. It fits a wide range of Mazda 3 passenger and Sport (hatchback) model years, and uses the same mounting points and hose connections as the OEM unit.

Will this reservoir fit my Mazda 3 or Mazda 3 Sport?

This reservoir is made to match factory dimensions for many Mazda 3 vehicles. Confirm fitment by checking model year and part references to ensure a correct match before ordering.

• Compatible with Mazda 3 model years 2004 through 2013.
• Specifically listed for 2009–2013 Mazda 3 Sport/hatchback variants.
• Replaces OEM part numbers including 603-043, 5M5H8K218AA and LF5015350 series.

How durable is this replacement coolant tank under engine heat and vibration?

The reservoir is molded from reinforced PA plastic chosen for its stability in automotive environments. That material offers good thermal resistance and toughness, reducing the chance of warping, cracking, or leaking compared with aged original tanks.

• Constructed from high-grade polyamide (PA) for heat and chemical resistance.
• Corrosion-resistant design helps prevent coolant contamination and failure.
• Factory-style mounting points and hose fittings maintain secure installation.

What comes in the box and is installation difficult?

The package contains the coolant overflow reservoir tank and its cap, ready for a straightforward replacement using common hand tools. The unit is intended as a drop-in substitute for the original tank, minimizing modification or fabrication.

• Includes 1x radiator coolant overflow reservoir tank and 1x cap.
• Designed for bolt-on installation using existing mounting points and hoses.
• Typical replacement time: under one hour for most DIYers or a quick job for a technician.

How can I confirm this is the right part if I have an older or later Mazda 3?

Compare your current reservoir’s shape, mounting and hose locations to product images and the OEM reference numbers. If your tank uses any of the listed replacement part numbers, this YzusGomumu unit will be a compatible match.

• Check for matching OEM numbers: 603-043, 5M5H8K218AA, LF5015350 (and variants).
• Verify hose inlet/outlet positions and mounting tab locations against photos.
• Contact seller with your VIN for final fit confirmation if unsure.

Who is this for: This replacement reservoir is aimed at Mazda 3 owners and mechanics who need an affordable, OEM-style spare part to replace a cracked or leaking coolant overflow tank. It suits do-it-yourself vehicle maintainers and professional shops looking for a durable PA-plastic replacement that matches factory fitment for 2004–2013 Mazda 3 sedans and 2009–2013 Sport models. Choose this tank when you want a corrosion-resistant, ready-to-install component that restores proper coolant overflow and return performance without custom fabrication.