Dorman 603-221 Engine Coolant Reservoir with Cap

The Dorman 603-221 is a direct-replacement engine coolant reservoir engineered to match the fit and function of the original equipment part. Manufactured from durable, heat-resistant plastic, this coolant overflow tank is built to withstand the demanding underhood environment — resisting expansion, cracking, and fluid loss caused by extreme temperature fluctuations and engine vibration.

Key Features:

• Direct OE Replacement: Engineered to match the original reservoir's mounting points, hose connections, and dimensions for a seamless, hassle-free installation
• Durable Construction: High-quality plastic resists underhood heat, vibration, and coolant fluid degradation
• Complete Assembly: Includes the reservoir and reservoir cap — everything needed for a complete replacement
• Quality Tested: Thoroughly inspected to ensure optimum fit and trouble-free performance
• Trusted Brand: Backed by Dorman's 100+ years of automotive aftermarket engineering experience

The Dorman 603-221 coolant reservoir — also known as a coolant recovery tank or coolant overflow bottle — restores proper coolant level management to your engine's cooling system. By collecting and returning excess coolant as the engine heats and cools, it helps prevent overheating and protects the engine from coolant loss. This is a cost-effective, reliable alternative to purchasing an expensive OEM part.